refactor: replace char_u with char

Work on https://github.com/neovim/neovim/issues/459

76 files changed, 868 insertions, 883 deletions

diff --git a/src/nvim/api/buffer.c b/src/nvim/api/buffer.c
index 16f574f46d..6f8cad3e33 100644
--- a/src/nvim/api/buffer.c
+++ b/src/nvim/api/buffer.c
@@ -570,7 +570,7 @@ void nvim_buf_set_text(uint64_t channel_id, Buffer buffer, Integer start_row, In
   char *str_at_end = NULL;
 
   // Another call to ml_get_buf() may free the line, so make a copy.
-  str_at_start = xstrdup((char *)ml_get_buf(buf, (linenr_T)start_row, false));
+  str_at_start = xstrdup(ml_get_buf(buf, (linenr_T)start_row, false));
   size_t len_at_start = strlen(str_at_start);
   if (start_col < 0 || (size_t)start_col > len_at_start) {
     api_set_error(err, kErrorTypeValidation, "start_col out of bounds");
@@ -578,7 +578,7 @@ void nvim_buf_set_text(uint64_t channel_id, Buffer buffer, Integer start_row, In
   }
 
   // Another call to ml_get_buf() may free the line, so make a copy.
-  str_at_end = xstrdup((char *)ml_get_buf(buf, (linenr_T)end_row, false));
+  str_at_end = xstrdup(ml_get_buf(buf, (linenr_T)end_row, false));
   size_t len_at_end = strlen(str_at_end);
   if (end_col < 0 || (size_t)end_col > len_at_end) {
     api_set_error(err, kErrorTypeValidation, "end_col out of bounds");
@@ -608,7 +608,7 @@ void nvim_buf_set_text(uint64_t channel_id, Buffer buffer, Integer start_row, In
     for (int64_t i = 1; i < end_row - start_row; i++) {
       int64_t lnum = start_row + i;
 
-      const char *bufline = (char *)ml_get_buf(buf, (linenr_T)lnum, false);
+      const char *bufline = ml_get_buf(buf, (linenr_T)lnum, false);
       old_byte += (bcount_t)(strlen(bufline)) + 1;
     }
     old_byte += (bcount_t)end_col + 1;
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index ebcf6cca6d..22d2ffbaf1 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -466,7 +466,7 @@ bool buf_collect_lines(buf_T *buf, size_t n, int64_t start, bool replace_nl, Arr
       return false;
     }
 
-    const char *bufstr = (char *)ml_get_buf(buf, (linenr_T)lnum, false);
+    const char *bufstr = ml_get_buf(buf, (linenr_T)lnum, false);
     Object str = STRING_OBJ(cstr_to_string(bufstr));
 
     if (replace_nl) {
@@ -499,7 +499,7 @@ String buf_get_text(buf_T *buf, int64_t lnum, int64_t start_col, int64_t end_col
     return rv;
   }
 
-  const char *bufstr = (char *)ml_get_buf(buf, (linenr_T)lnum, false);
+  const char *bufstr = ml_get_buf(buf, (linenr_T)lnum, false);
   size_t line_length = strlen(bufstr);
 
   start_col = start_col < 0 ? (int64_t)line_length + start_col + 1 : start_col;
diff --git a/src/nvim/arglist.c b/src/nvim/arglist.c
index e6ac1f6247..0000636417 100644
--- a/src/nvim/arglist.c
+++ b/src/nvim/arglist.c
@@ -86,7 +86,7 @@ void alist_expand(int *fnum_list, int fnum_len)
   // can't set the options.
   p_su = empty_option;
   for (int i = 0; i < GARGCOUNT; i++) {
-    old_arg_files[i] = vim_strsave(GARGLIST[i].ae_fname);
+    old_arg_files[i] = xstrdup(GARGLIST[i].ae_fname);
   }
   int old_arg_count = GARGCOUNT;
   char **new_arg_files;
diff --git a/src/nvim/autocmd.c b/src/nvim/autocmd.c
index 1c1de214cd..635875b16f 100644
--- a/src/nvim/autocmd.c
+++ b/src/nvim/autocmd.c
@@ -2214,7 +2214,7 @@ bool has_autocmd(event_T event, char *sfname, buf_T *buf)
 #ifdef BACKSLASH_IN_FILENAME
   // Replace all backslashes with forward slashes. This makes the
   // autocommand patterns portable between Unix and Windows.
-  sfname = vim_strsave(sfname);
+  sfname = xstrdup(sfname);
   forward_slash(sfname);
   forward_slash(fname);
 #endif
diff --git a/src/nvim/change.c b/src/nvim/change.c
index 5e9edac4f2..f4568fc617 100644
--- a/src/nvim/change.c
+++ b/src/nvim/change.c
@@ -774,7 +774,7 @@ int del_char(bool fixpos)
 int del_chars(long count, int fixpos)
 {
   int bytes = 0;
-  char *p = (char *)get_cursor_pos_ptr();
+  char *p = get_cursor_pos_ptr();
   for (long i = 0; i < count && *p != NUL; i++) {
     int l = utfc_ptr2len(p);
     bytes += l;
@@ -1036,7 +1036,7 @@ int open_line(int dir, int flags, int second_line_indent, bool *did_do_comment)
   colnr_T mincol = curwin->w_cursor.col + 1;
 
   // make a copy of the current line so we can mess with it
-  char *saved_line = (char *)vim_strsave((char_u *)get_cursor_line_ptr());
+  char *saved_line = xstrdup(get_cursor_line_ptr());
 
   if (State & VREPLACE_FLAG) {
     // With MODE_VREPLACE we make a copy of the next line, which we will be
diff --git a/src/nvim/charset.c b/src/nvim/charset.c
index 3396e2de41..693ff90179 100644
--- a/src/nvim/charset.c
+++ b/src/nvim/charset.c
@@ -913,7 +913,7 @@ void getvcol(win_T *wp, pos_T *pos, colnr_T *start, colnr_T *cursor, colnr_T *en
   int ts = (int)wp->w_buffer->b_p_ts;
 
   colnr_T vcol = 0;
-  char *line = ptr = (char *)ml_get_buf(wp->w_buffer, pos->lnum, false);  // start of the line
+  char *line = ptr = ml_get_buf(wp->w_buffer, pos->lnum, false);  // start of the line
 
   if (pos->col == MAXCOL) {
     // continue until the NUL
@@ -1076,7 +1076,7 @@ void getvvcol(win_T *wp, pos_T *pos, colnr_T *start, colnr_T *cursor, colnr_T *e
     colnr_T endadd = 0;
 
     // Cannot put the cursor on part of a wide character.
-    char *ptr = (char *)ml_get_buf(wp->w_buffer, pos->lnum, false);
+    char *ptr = ml_get_buf(wp->w_buffer, pos->lnum, false);
 
     if (pos->col < (colnr_T)STRLEN(ptr)) {
       int c = utf_ptr2char(ptr + pos->col);
diff --git a/src/nvim/cmdexpand.c b/src/nvim/cmdexpand.c
index 30e734b93f..3f624c77f3 100644
--- a/src/nvim/cmdexpand.c
+++ b/src/nvim/cmdexpand.c
@@ -183,7 +183,7 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
 
   if (type == WILD_NEXT || type == WILD_PREV) {
     // Get next/previous match for a previous expanded pattern.
-    p2 = ExpandOne(xp, NULL, NULL, 0, type);
+    p2 = (char_u *)ExpandOne(xp, NULL, NULL, 0, type);
   } else {
     // Translate string into pattern and expand it.
     p1 = (char_u *)addstar(xp->xp_pattern, xp->xp_pattern_len, xp->xp_context);
@@ -193,8 +193,8 @@ int nextwild(expand_T *xp, int type, int options, bool escape)
                              | WILD_SILENT
                              | (escape ? WILD_ESCAPE : 0)
                              | (p_wic ? WILD_ICASE : 0));
-    p2 = ExpandOne(xp, p1, (char_u *)xstrnsave(&ccline->cmdbuff[i], xp->xp_pattern_len),
-                   use_options, type);
+    p2 = (char_u *)ExpandOne(xp, (char *)p1, xstrnsave(&ccline->cmdbuff[i], xp->xp_pattern_len),
+                             use_options, type);
     xfree(p1);
 
     // xp->xp_pattern might have been modified by ExpandOne (for example,
@@ -278,7 +278,7 @@ void cmdline_pum_cleanup(CmdlineInfo *cclp)
 
 /// Get the next or prev cmdline completion match. The index of the match is set
 /// in "p_findex"
-static char_u *get_next_or_prev_match(int mode, expand_T *xp, int *p_findex, char_u *orig_save)
+static char *get_next_or_prev_match(int mode, expand_T *xp, int *p_findex, char *orig_save)
 {
   if (xp->xp_numfiles <= 0) {
     return NULL;
@@ -318,17 +318,17 @@ static char_u *get_next_or_prev_match(int mode, expand_T *xp, int *p_findex, cha
   }
   *p_findex = findex;
 
-  return vim_strsave(findex == -1 ? orig_save : (char_u *)xp->xp_files[findex]);
+  return xstrdup(findex == -1 ? orig_save : xp->xp_files[findex]);
 }
 
 /// Start the command-line expansion and get the matches.
-static char_u *ExpandOne_start(int mode, expand_T *xp, char_u *str, int options)
+static char *ExpandOne_start(int mode, expand_T *xp, char *str, int options)
 {
   int non_suf_match;  // number without matching suffix
-  char_u *ss = NULL;
+  char *ss = NULL;
 
   // Do the expansion.
-  if (ExpandFromContext(xp, str, &xp->xp_numfiles, &xp->xp_files, options) == FAIL) {
+  if (ExpandFromContext(xp, (char_u *)str, &xp->xp_numfiles, &xp->xp_files, options) == FAIL) {
 #ifdef FNAME_ILLEGAL
     // Illegal file name has been silently skipped.  But when there
     // are wildcards, the real problem is that there was no match,
@@ -343,7 +343,7 @@ static char_u *ExpandOne_start(int mode, expand_T *xp, char_u *str, int options)
     }
   } else {
     // Escape the matches for use on the command line.
-    ExpandEscape(xp, str, xp->xp_numfiles, xp->xp_files, options);
+    ExpandEscape(xp, (char_u *)str, xp->xp_numfiles, xp->xp_files, options);
 
     // Check for matching suffixes in file names.
     if (mode != WILD_ALL && mode != WILD_ALL_KEEP
@@ -378,7 +378,7 @@ static char_u *ExpandOne_start(int mode, expand_T *xp, char_u *str, int options)
         }
       }
       if (!(non_suf_match != 1 && mode == WILD_EXPAND_FREE)) {
-        ss = vim_strsave((char_u *)xp->xp_files[0]);
+        ss = xstrdup(xp->xp_files[0]);
       }
     }
   }
@@ -458,11 +458,11 @@ static char *find_longest_match(expand_T *xp, int options)
 /// The variables xp->xp_context and xp->xp_backslash must have been set!
 ///
 /// @param orig  allocated copy of original of expanded string
-char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode)
+char *ExpandOne(expand_T *xp, char *str, char *orig, int options, int mode)
 {
-  char_u *ss = NULL;
+  char *ss = NULL;
   static int findex;
-  static char_u *orig_save = NULL;      // kept value of orig
+  static char *orig_save = NULL;      // kept value of orig
   int orig_saved = false;
   int i;
 
@@ -472,10 +472,11 @@ char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode
   }
 
   if (mode == WILD_CANCEL) {
-    ss = vim_strsave(orig_save ? orig_save : (char_u *)"");
+    ss = xstrdup(orig_save ? orig_save : "");
   } else if (mode == WILD_APPLY) {
-    ss = vim_strsave(findex == -1 ? (orig_save ? orig_save : (char_u *)"")
-                     : (char_u *)xp->xp_files[findex]);
+    ss = xstrdup(findex == -1
+                 ? (orig_save ? orig_save : "")
+                 : xp->xp_files[findex]);
   }
 
   // free old names
@@ -500,7 +501,7 @@ char_u *ExpandOne(expand_T *xp, char_u *str, char_u *orig, int options, int mode
 
   // Find longest common part
   if (mode == WILD_LONGEST && xp->xp_numfiles > 0) {
-    ss = (char_u *)find_longest_match(xp, options);
+    ss = find_longest_match(xp, options);
     findex = -1;  // next p_wc gets first one
   }
 
@@ -1915,7 +1916,7 @@ int expand_cmdline(expand_T *xp, char_u *str, int col, int *matchcount, char ***
 }
 
 /// Expand file or directory names.
-static int expand_files_and_dirs(expand_T *xp, char_u *pat, char ***file, int *num_file, int flags,
+static int expand_files_and_dirs(expand_T *xp, char *pat, char ***file, int *num_file, int flags,
                                  int options)
 {
   bool free_pat = false;
@@ -1923,7 +1924,7 @@ static int expand_files_and_dirs(expand_T *xp, char_u *pat, char ***file, int *n
   // for ":set path=" and ":set tags=" halve backslashes for escaped space
   if (xp->xp_backslash != XP_BS_NONE) {
     free_pat = true;
-    pat = vim_strsave(pat);
+    pat = xstrdup(pat);
     for (int i = 0; pat[i]; i++) {
       if (pat[i] == '\\') {
         if (xp->xp_backslash == XP_BS_THREE
@@ -2124,7 +2125,7 @@ static int ExpandFromContext(expand_T *xp, char_u *pat, int *num_file, char ***f
   if (xp->xp_context == EXPAND_FILES
       || xp->xp_context == EXPAND_DIRECTORIES
       || xp->xp_context == EXPAND_FILES_IN_PATH) {
-    return expand_files_and_dirs(xp, pat, file, num_file, flags, options);
+    return expand_files_and_dirs(xp, (char *)pat, file, num_file, flags, options);
   }
 
   *file = NULL;
@@ -2142,7 +2143,7 @@ static int ExpandFromContext(expand_T *xp, char_u *pat, int *num_file, char ***f
 
   if (xp->xp_context == EXPAND_SHELLCMD) {
     *file = NULL;
-    expand_shellcmd(pat, num_file, file, flags);
+    expand_shellcmd((char *)pat, num_file, file, flags);
     return OK;
   }
   if (xp->xp_context == EXPAND_OLD_SETTING) {
@@ -2238,18 +2239,18 @@ static void ExpandGeneric(expand_T *xp, regmatch_T *regmatch, int *num_file, cha
 {
   int i;
   size_t count = 0;
-  char_u *str;
+  char *str;
 
   // count the number of matching names
   for (i = 0;; i++) {
-    str = (char_u *)(*func)(xp, i);
+    str = (*func)(xp, i);
     if (str == NULL) {  // end of list
       break;
     }
     if (*str == NUL) {  // skip empty strings
       continue;
     }
-    if (vim_regexec(regmatch, (char *)str, (colnr_T)0)) {
+    if (vim_regexec(regmatch, str, (colnr_T)0)) {
       count++;
     }
   }
@@ -2263,20 +2264,20 @@ static void ExpandGeneric(expand_T *xp, regmatch_T *regmatch, int *num_file, cha
   // copy the matching names into allocated memory
   count = 0;
   for (i = 0;; i++) {
-    str = (char_u *)(*func)(xp, i);
+    str = (*func)(xp, i);
     if (str == NULL) {  // End of list.
       break;
     }
     if (*str == NUL) {  // Skip empty strings.
       continue;
     }
-    if (vim_regexec(regmatch, (char *)str, (colnr_T)0)) {
+    if (vim_regexec(regmatch, str, (colnr_T)0)) {
       if (escaped) {
-        str = vim_strsave_escaped(str, (char_u *)" \t\\.");
+        str = (char *)vim_strsave_escaped((char_u *)str, (char_u *)" \t\\.");
       } else {
-        str = vim_strsave(str);
+        str = xstrdup(str);
       }
-      (*file)[count++] = (char *)str;
+      (*file)[count++] = str;
       if (func == get_menu_names) {
         // Test for separator added by get_menu_names().
         str += STRLEN(str) - 1;
@@ -2313,22 +2314,22 @@ static void ExpandGeneric(expand_T *xp, regmatch_T *regmatch, int *num_file, cha
 ///                      *file will either be set to NULL or point to
 ///                      allocated memory.
 /// @param      flagsarg is a combination of EW_* flags.
-static void expand_shellcmd(char_u *filepat, int *num_file, char ***file, int flagsarg)
+static void expand_shellcmd(char *filepat, int *num_file, char ***file, int flagsarg)
   FUNC_ATTR_NONNULL_ALL
 {
-  char_u *pat;
+  char *pat;
   int i;
-  char_u *path = NULL;
+  char *path = NULL;
   garray_T ga;
   char *buf = xmalloc(MAXPATHL);
   size_t l;
-  char_u *s, *e;
+  char *s, *e;
   int flags = flagsarg;
   int ret;
   bool did_curdir = false;
 
   // for ":set path=" and ":set tags=" halve backslashes for escaped space
-  pat = vim_strsave(filepat);
+  pat = xstrdup(filepat);
   for (i = 0; pat[i]; i++) {
     if (pat[i] == '\\' && pat[i + 1] == ' ') {
       STRMOVE(pat + i, pat + i + 1);
@@ -2340,14 +2341,14 @@ static void expand_shellcmd(char_u *filepat, int *num_file, char ***file, int fl
   bool mustfree = false;  // Track memory allocation for *path.
   if (pat[0] == '.' && (vim_ispathsep(pat[1])
                         || (pat[1] == '.' && vim_ispathsep(pat[2])))) {
-    path = (char_u *)".";
+    path = ".";
   } else {
     // For an absolute name we don't use $PATH.
-    if (!path_is_absolute(pat)) {
-      path = (char_u *)vim_getenv("PATH");
+    if (!path_is_absolute((char_u *)pat)) {
+      path = vim_getenv("PATH");
     }
     if (path == NULL) {
-      path = (char_u *)"";
+      path = "";
     } else {
       mustfree = true;
     }
@@ -2360,7 +2361,7 @@ static void expand_shellcmd(char_u *filepat, int *num_file, char ***file, int fl
   hashtab_T found_ht;
   hash_init(&found_ht);
   for (s = path;; s = e) {
-    e = (char_u *)vim_strchr((char *)s, ENV_SEPCHAR);
+    e = vim_strchr(s, ENV_SEPCHAR);
     if (e == NULL) {
       e = s + STRLEN(s);
     }
@@ -2895,7 +2896,7 @@ void f_getcompletion(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 
 theend:
   pat = (char_u *)addstar(xpc.xp_pattern, xpc.xp_pattern_len, xpc.xp_context);
-  ExpandOne(&xpc, pat, NULL, options, WILD_ALL_KEEP);
+  ExpandOne(&xpc, (char *)pat, NULL, options, WILD_ALL_KEEP);
   tv_list_alloc_ret(rettv, xpc.xp_numfiles);
 
   for (int i = 0; i < xpc.xp_numfiles; i++) {
diff --git a/src/nvim/cmdhist.c b/src/nvim/cmdhist.c
index 629c47f24a..38353f44b5 100644
--- a/src/nvim/cmdhist.c
+++ b/src/nvim/cmdhist.c
@@ -382,13 +382,13 @@ static int calc_hist_idx(int histype, int num)
 /// Get a history entry by its index.
 ///
 /// @param histype  may be one of the HIST_ values.
-static char_u *get_history_entry(int histype, int idx)
+static char *get_history_entry(int histype, int idx)
 {
   idx = calc_hist_idx(histype, idx);
   if (idx >= 0) {
-    return (char_u *)history[histype][idx].hisstr;
+    return history[histype][idx].hisstr;
   } else {
-    return (char_u *)"";
+    return "";
   }
 }
 
@@ -556,7 +556,7 @@ void f_histget(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
       idx = (int)tv_get_number_chk(&argvars[1], NULL);
     }
     // -1 on type error
-    rettv->vval.v_string = (char *)vim_strsave(get_history_entry(type, idx));
+    rettv->vval.v_string = xstrdup(get_history_entry(type, idx));
   }
   rettv->v_type = VAR_STRING;
 }
diff --git a/src/nvim/cursor.c b/src/nvim/cursor.c
index 2a3fe9701c..cd651fcf4c 100644
--- a/src/nvim/cursor.c
+++ b/src/nvim/cursor.c
@@ -101,7 +101,7 @@ static int coladvance2(pos_T *pos, bool addspaces, bool finetune, colnr_T wcol_a
                  || (VIsual_active && *p_sel != 'o')
                  || ((get_ve_flags() & VE_ONEMORE) && wcol < MAXCOL);
 
-  char_u *line = ml_get_buf(curbuf, pos->lnum, false);
+  char_u *line = (char_u *)ml_get_buf(curbuf, pos->lnum, false);
 
   if (wcol >= MAXCOL) {
     idx = (int)STRLEN(line) - 1 + one_more;
@@ -308,7 +308,7 @@ void check_pos(buf_T *buf, pos_T *pos)
   }
 
   if (pos->col > 0) {
-    char_u *line = ml_get_buf(buf, pos->lnum, false);
+    char_u *line = (char_u *)ml_get_buf(buf, pos->lnum, false);
     colnr_T len = (colnr_T)STRLEN(line);
     if (pos->col > len) {
       pos->col = len;
@@ -481,7 +481,7 @@ bool leftcol_changed(void)
 
 int gchar_cursor(void)
 {
-  return utf_ptr2char((char *)get_cursor_pos_ptr());
+  return utf_ptr2char(get_cursor_pos_ptr());
 }
 
 /// Write a character at the current cursor position.
@@ -489,18 +489,17 @@ int gchar_cursor(void)
 void pchar_cursor(char_u c)
 {
   *(ml_get_buf(curbuf, curwin->w_cursor.lnum, true)
-    + curwin->w_cursor.col) = c;
+    + curwin->w_cursor.col) = (char)c;
 }
 
 /// @return  pointer to cursor line.
 char *get_cursor_line_ptr(void)
 {
-  return (char *)ml_get_buf(curbuf, curwin->w_cursor.lnum, false);
+  return ml_get_buf(curbuf, curwin->w_cursor.lnum, false);
 }
 
 /// @return  pointer to cursor position.
-char_u *get_cursor_pos_ptr(void)
+char *get_cursor_pos_ptr(void)
 {
-  return ml_get_buf(curbuf, curwin->w_cursor.lnum, false) +
-         curwin->w_cursor.col;
+  return ml_get_buf(curbuf, curwin->w_cursor.lnum, false) + curwin->w_cursor.col;
 }
diff --git a/src/nvim/diff.c b/src/nvim/diff.c
index a3046bb7d7..69883966ab 100644
--- a/src/nvim/diff.c
+++ b/src/nvim/diff.c
@@ -573,9 +573,9 @@ static void diff_check_unchanged(tabpage_T *tp, diff_T *dp)
       if (dir == BACKWARD) {
         off_org = dp->df_count[i_org] - 1;
       }
-      char *line_org = (char *)vim_strsave(ml_get_buf(tp->tp_diffbuf[i_org],
-                                                      dp->df_lnum[i_org] + off_org,
-                                                      false));
+      char *line_org = xstrdup(ml_get_buf(tp->tp_diffbuf[i_org],
+                                          dp->df_lnum[i_org] + off_org,
+                                          false));
 
       int i_new;
       for (i_new = i_org + 1; i_new < DB_COUNT; i_new++) {
@@ -592,9 +592,9 @@ static void diff_check_unchanged(tabpage_T *tp, diff_T *dp)
           break;
         }
 
-        if (diff_cmp((char_u *)line_org, ml_get_buf(tp->tp_diffbuf[i_new],
-                                                    dp->df_lnum[i_new] + off_new,
-                                                    false)) != 0) {
+        if (diff_cmp((char_u *)line_org, (char_u *)ml_get_buf(tp->tp_diffbuf[i_new],
+                                                              dp->df_lnum[i_new] + off_new,
+                                                              false)) != 0) {
           break;
         }
       }
@@ -750,7 +750,7 @@ static int diff_write_buffer(buf_T *buf, diffin_T *din)
 
   len = 0;
   for (linenr_T lnum = 1; lnum <= buf->b_ml.ml_line_count; lnum++) {
-    for (char_u *s = ml_get_buf(buf, lnum, false); *s != NUL;) {
+    for (char_u *s = (char_u *)ml_get_buf(buf, lnum, false); *s != NUL;) {
       if (diff_flags & DIFF_ICASE) {
         int c;
         char cbuf[MB_MAXBYTES + 1];
@@ -824,9 +824,9 @@ static void diff_try_update(diffio_T *dio, int idx_orig, exarg_T *eap)
     ga_init(&dio->dio_diff.dout_ga, sizeof(char *), 1000);
   } else {
     // We need three temp file names.
-    dio->dio_orig.din_fname = vim_tempname();
-    dio->dio_new.din_fname = vim_tempname();
-    dio->dio_diff.dout_fname = vim_tempname();
+    dio->dio_orig.din_fname = (char_u *)vim_tempname();
+    dio->dio_new.din_fname = (char_u *)vim_tempname();
+    dio->dio_diff.dout_fname = (char_u *)vim_tempname();
     if (dio->dio_orig.din_fname == NULL
         || dio->dio_new.din_fname == NULL
         || dio->dio_diff.dout_fname == NULL) {
@@ -1178,9 +1178,9 @@ void ex_diffpatch(exarg_T *eap)
 
   // We need two temp file names.
   // Name of original temp file.
-  char_u *tmp_orig = vim_tempname();
+  char_u *tmp_orig = (char_u *)vim_tempname();
   // Name of patched temp file.
-  char_u *tmp_new = vim_tempname();
+  char_u *tmp_new = (char_u *)vim_tempname();
 
   if ((tmp_orig == NULL) || (tmp_new == NULL)) {
     goto theend;
@@ -1920,11 +1920,11 @@ static bool diff_equal_entry(diff_T *dp, int idx1, int idx2)
   }
 
   for (int i = 0; i < dp->df_count[idx1]; i++) {
-    char *line = (char *)vim_strsave(ml_get_buf(curtab->tp_diffbuf[idx1],
-                                                dp->df_lnum[idx1] + i, false));
+    char *line = xstrdup(ml_get_buf(curtab->tp_diffbuf[idx1],
+                                    dp->df_lnum[idx1] + i, false));
 
-    int cmp = diff_cmp((char_u *)line, ml_get_buf(curtab->tp_diffbuf[idx2],
-                                                  dp->df_lnum[idx2] + i, false));
+    int cmp = diff_cmp((char_u *)line, (char_u *)ml_get_buf(curtab->tp_diffbuf[idx2],
+                                                            dp->df_lnum[idx2] + i, false));
     xfree(line);
 
     if (cmp != 0) {
@@ -2290,7 +2290,7 @@ bool diff_find_change(win_T *wp, linenr_T lnum, int *startp, int *endp)
   int l;
 
   // Make a copy of the line, the next ml_get() will invalidate it.
-  char *line_org = (char *)vim_strsave(ml_get_buf(wp->w_buffer, lnum, false));
+  char *line_org = xstrdup(ml_get_buf(wp->w_buffer, lnum, false));
 
   int idx = diff_buf_idx(wp->w_buffer);
   if (idx == DB_COUNT) {
@@ -2322,8 +2322,7 @@ bool diff_find_change(win_T *wp, linenr_T lnum, int *startp, int *endp)
         continue;
       }
       added = false;
-      line_new = (char *)ml_get_buf(curtab->tp_diffbuf[i],
-                                    dp->df_lnum[i] + off, false);
+      line_new = ml_get_buf(curtab->tp_diffbuf[i], dp->df_lnum[i] + off, false);
 
       // Search for start of difference
       si_org = si_new = 0;
@@ -2718,7 +2717,7 @@ void ex_diffgetput(exarg_T *eap)
         if (nr > curtab->tp_diffbuf[idx_from]->b_ml.ml_line_count) {
           break;
         }
-        p = (char *)vim_strsave(ml_get_buf(curtab->tp_diffbuf[idx_from], nr, false));
+        p = xstrdup(ml_get_buf(curtab->tp_diffbuf[idx_from], nr, false));
         ml_append(lnum + i - 1, p, 0, false);
         xfree(p);
         added++;
diff --git a/src/nvim/digraph.c b/src/nvim/digraph.c
index 53b6c66c46..8e31d3feab 100644
--- a/src/nvim/digraph.c
+++ b/src/nvim/digraph.c
@@ -1932,9 +1932,9 @@ void f_digraph_get(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
   int code = digraph_get(digraphs[0], digraphs[1], false);
 
-  char_u buf[NUMBUFLEN];
-  buf[utf_char2bytes(code, (char *)buf)] = NUL;
-  rettv->vval.v_string = (char *)vim_strsave(buf);
+  char buf[NUMBUFLEN];
+  buf[utf_char2bytes(code, buf)] = NUL;
+  rettv->vval.v_string = xstrdup(buf);
 }
 
 /// "digraph_getlist()" function
diff --git a/src/nvim/drawline.c b/src/nvim/drawline.c
index 7846510ad9..9de8b9996a 100644
--- a/src/nvim/drawline.c
+++ b/src/nvim/drawline.c
@@ -689,7 +689,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
       // Trick: skip a few chars for C/shell/Vim comments
       nextline[SPWORDLEN] = NUL;
       if (lnum < wp->w_buffer->b_ml.ml_line_count) {
-        line = ml_get_buf(wp->w_buffer, lnum + 1, false);
+        line = (char_u *)ml_get_buf(wp->w_buffer, lnum + 1, false);
         spell_cat_line(nextline + SPWORDLEN, line, SPWORDLEN);
       }
 
@@ -866,7 +866,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
     line_attr_lowprio_save = line_attr_lowprio;
   }
 
-  line = end_fill ? (char_u *)"" : ml_get_buf(wp->w_buffer, lnum, false);
+  line = end_fill ? (char_u *)"" : (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
   ptr = line;
 
   if (has_spell && !number_only) {
@@ -1006,7 +1006,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
       len = spell_move_to(wp, FORWARD, true, true, &spell_hlf);
 
       // spell_move_to() may call ml_get() and make "line" invalid
-      line = ml_get_buf(wp->w_buffer, lnum, false);
+      line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
       ptr = line + linecol;
 
       if (len == 0 || (int)wp->w_cursor.col > ptr - line) {
@@ -1224,7 +1224,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
           c_extra = ' ';
           c_final = NUL;
           n_extra =
-            get_breakindent_win(wp, ml_get_buf(wp->w_buffer, lnum, false));
+            get_breakindent_win(wp, (char_u *)ml_get_buf(wp->w_buffer, lnum, false));
           if (row == startrow) {
             n_extra -= win_col_off2(wp);
             if (n_extra < 0) {
@@ -1676,7 +1676,7 @@ int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow, bool nochange,
 
           // Need to get the line again, a multi-line regexp may
           // have made it invalid.
-          line = ml_get_buf(wp->w_buffer, lnum, false);
+          line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
           ptr = line + v;
 
           if (!attr_pri) {
diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index b20fc7d44a..f7a16abfb2 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -1439,21 +1439,21 @@ void edit_putchar(int c, bool highlight)
   }
 }
 
-/// Return the effective prompt for the specified buffer.
-char_u *buf_prompt_text(const buf_T *const buf)
+/// @return    the effective prompt for the specified buffer.
+char *buf_prompt_text(const buf_T *const buf)
     FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE
 {
   if (buf->b_prompt_text == NULL) {
-    return (char_u *)"% ";
+    return "% ";
   }
-  return (char_u *)buf->b_prompt_text;
+  return buf->b_prompt_text;
 }
 
 // Return the effective prompt for the current buffer.
 char_u *prompt_text(void)
   FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_PURE
 {
-  return buf_prompt_text(curbuf);
+  return (char_u *)buf_prompt_text(curbuf);
 }
 
 // Prepare for prompt mode: Make sure the last line has the prompt text.
@@ -1574,11 +1574,11 @@ void change_indent(int type, int amount, int round, int replaced, int call_chang
   int start_col;
   colnr_T vc;
   colnr_T orig_col = 0;                 // init for GCC
-  char_u *new_line, *orig_line = NULL;     // init for GCC
+  char *new_line, *orig_line = NULL;     // init for GCC
 
   // MODE_VREPLACE state needs to know what the line was like before changing
   if (State & VREPLACE_FLAG) {
-    orig_line = vim_strsave((char_u *)get_cursor_line_ptr());   // Deal with NULL below
+    orig_line = xstrdup(get_cursor_line_ptr());   // Deal with NULL below
     orig_col = curwin->w_cursor.col;
   }
 
@@ -1733,14 +1733,14 @@ void change_indent(int type, int amount, int round, int replaced, int call_chang
   // then put it back again the way we wanted it.
   if (State & VREPLACE_FLAG) {
     // Save new line
-    new_line = vim_strsave((char_u *)get_cursor_line_ptr());
+    new_line = xstrdup(get_cursor_line_ptr());
 
     // We only put back the new line up to the cursor
     new_line[curwin->w_cursor.col] = NUL;
     int new_col = curwin->w_cursor.col;
 
     // Put back original line
-    ml_replace(curwin->w_cursor.lnum, (char *)orig_line, false);
+    ml_replace(curwin->w_cursor.lnum, orig_line, false);
     curwin->w_cursor.col = orig_col;
 
     curbuf_splice_pending++;
@@ -1749,7 +1749,7 @@ void change_indent(int type, int amount, int round, int replaced, int call_chang
     backspace_until_column(0);
 
     // Insert new stuff into line again
-    ins_bytes((char *)new_line);
+    ins_bytes(new_line);
 
     xfree(new_line);
 
@@ -1813,7 +1813,7 @@ static bool del_char_after_col(int limit_col)
     // composing character.
     mb_adjust_cursor();
     while (curwin->w_cursor.col < (colnr_T)limit_col) {
-      int l = utf_ptr2len((char *)get_cursor_pos_ptr());
+      int l = utf_ptr2len(get_cursor_pos_ptr());
 
       if (l == 0) {  // end of line
         break;
@@ -2466,7 +2466,7 @@ int oneright(void)
     pos_T prevpos = curwin->w_cursor;
 
     // Adjust for multi-wide char (excluding TAB)
-    ptr = (char *)get_cursor_pos_ptr();
+    ptr = get_cursor_pos_ptr();
     coladvance(getviscol() + ((*ptr != TAB && vim_isprintc(utf_ptr2char(ptr))) ?
                               ptr2cells(ptr) : 1));
     curwin->w_set_curswant = true;
@@ -2475,7 +2475,7 @@ int oneright(void)
             || prevpos.coladd != curwin->w_cursor.coladd) ? OK : FAIL;
   }
 
-  ptr = (char *)get_cursor_pos_ptr();
+  ptr = get_cursor_pos_ptr();
   if (*ptr == NUL) {
     return FAIL;            // already at the very end
   }
@@ -2518,7 +2518,7 @@ int oneleft(void)
 
     if (curwin->w_cursor.coladd == 1) {
       // Adjust for multi-wide char (not a TAB)
-      char *ptr = (char *)get_cursor_pos_ptr();
+      char *ptr = get_cursor_pos_ptr();
       if (*ptr != TAB && vim_isprintc(utf_ptr2char(ptr)) && ptr2cells(ptr) > 1) {
         curwin->w_cursor.coladd = 0;
       }
@@ -2720,19 +2720,19 @@ char_u *get_last_insert(void)
 // Returns pointer to allocated memory (must be freed) or NULL.
 char_u *get_last_insert_save(void)
 {
-  char_u *s;
+  char *s;
   int len;
 
   if (last_insert == NULL) {
     return NULL;
   }
-  s = vim_strsave(last_insert + last_insert_skip);
+  s = xstrdup((char *)last_insert + last_insert_skip);
   len = (int)STRLEN(s);
   if (len > 0 && s[len - 1] == ESC) {         // remove trailing ESC
     s[len - 1] = NUL;
   }
 
-  return s;
+  return (char_u *)s;
 }
 
 /// Check the word in front of the cursor for an abbreviation.
@@ -2934,7 +2934,7 @@ static void replace_do_bs(int limit_col)
       // Get the number of screen cells used by the character we are
       // going to delete.
       getvcol(curwin, &curwin->w_cursor, NULL, &start_vcol, NULL);
-      orig_vcols = win_chartabsize(curwin, (char *)get_cursor_pos_ptr(), start_vcol);
+      orig_vcols = win_chartabsize(curwin, get_cursor_pos_ptr(), start_vcol);
     }
     (void)del_char_after_col(limit_col);
     if (l_State & VREPLACE_FLAG) {
@@ -2945,7 +2945,7 @@ static void replace_do_bs(int limit_col)
 
     if (l_State & VREPLACE_FLAG) {
       // Get the number of screen cells used by the inserted characters
-      p = get_cursor_pos_ptr();
+      p = (char_u *)get_cursor_pos_ptr();
       ins_len = (int)STRLEN(p) - orig_len;
       vcol = start_vcol;
       for (i = 0; i < ins_len; i++) {
@@ -3186,7 +3186,7 @@ bool in_cinkeys(int keytyped, int when, bool line_is_empty)
           if (keytyped == (int)p[-1]
               || (icase && keytyped < 256
                   && TOLOWER_LOC(keytyped) == TOLOWER_LOC((int)p[-1]))) {
-            line = get_cursor_pos_ptr();
+            line = (char_u *)get_cursor_pos_ptr();
             assert(p >= look && (uintmax_t)(p - look) <= SIZE_MAX);
             if ((curwin->w_cursor.col == (colnr_T)(p - look)
                  || !vim_iswordc(line[-(p - look) - 1]))
@@ -3880,7 +3880,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
         // again when auto-formatting.
         if (has_format_option(FO_AUTO)
             && has_format_option(FO_WHITE_PAR)) {
-          char_u *ptr = ml_get_buf(curbuf, curwin->w_cursor.lnum, true);
+          char_u *ptr = (char_u *)ml_get_buf(curbuf, curwin->w_cursor.lnum, true);
           int len;
 
           len = (int)STRLEN(ptr);
@@ -3974,7 +3974,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
 
       // delete characters until we are at or before want_vcol
       while (vcol > want_vcol && curwin->w_cursor.col > 0
-             && (cc = *(get_cursor_pos_ptr() - 1), ascii_iswhite(cc))) {
+             && (cc = (uint8_t)(*(get_cursor_pos_ptr() - 1)), ascii_iswhite(cc))) {
         ins_bs_one(&vcol);
       }
 
@@ -4006,7 +4006,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
       // Delete up to starting point, start of line or previous word.
       int prev_cclass = 0;
 
-      int cclass = mb_get_class(get_cursor_pos_ptr());
+      int cclass = mb_get_class((char_u *)get_cursor_pos_ptr());
       do {
         if (!revins_on) {   // put cursor on char to be deleted
           dec_cursor();
@@ -4014,7 +4014,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
         cc = gchar_cursor();
         // look multi-byte character class
         prev_cclass = cclass;
-        cclass = mb_get_class(get_cursor_pos_ptr());
+        cclass = mb_get_class((char_u *)get_cursor_pos_ptr());
         if (mode == BACKSPACE_WORD && !ascii_isspace(cc)) {   // start of word?
           mode = BACKSPACE_WORD_NOT_SPACE;
           temp = vim_iswordc(cc);
@@ -4033,7 +4033,7 @@ static bool ins_bs(int c, int mode, int *inserted_space_p)
         } else {
           const int l_p_deco = p_deco;
           if (l_p_deco) {
-            (void)utfc_ptr2char((char *)get_cursor_pos_ptr(), cpc);
+            (void)utfc_ptr2char(get_cursor_pos_ptr(), cpc);
           }
           (void)del_char(false);
           // If there are combining characters and 'delcombine' is set
@@ -4286,7 +4286,7 @@ static void ins_right(void)
     if (virtual_active()) {
       oneright();
     } else {
-      curwin->w_cursor.col += utfc_ptr2len((char *)get_cursor_pos_ptr());
+      curwin->w_cursor.col += utfc_ptr2len(get_cursor_pos_ptr());
     }
 
     revins_legal++;
@@ -4507,7 +4507,7 @@ static bool ins_tab(void)
                           || get_sts_value() > 0
                           || (p_sta && ind))) {
     char_u *ptr;
-    char_u *saved_line = NULL;         // init for GCC
+    char *saved_line = NULL;         // init for GCC
     pos_T pos;
     pos_T fpos;
     pos_T *cursor;
@@ -4520,10 +4520,10 @@ static bool ins_tab(void)
     if (State & VREPLACE_FLAG) {
       pos = curwin->w_cursor;
       cursor = &pos;
-      saved_line = vim_strsave((char_u *)get_cursor_line_ptr());
-      ptr = saved_line + pos.col;
+      saved_line = xstrdup(get_cursor_line_ptr());
+      ptr = (char_u *)saved_line + pos.col;
     } else {
-      ptr = get_cursor_pos_ptr();
+      ptr = (char_u *)get_cursor_pos_ptr();
       cursor = &curwin->w_cursor;
     }
 
@@ -4627,7 +4627,7 @@ static bool ins_tab(void)
 
         // Insert each char in saved_line from changed_col to
         // ptr-cursor
-        ins_bytes_len((char *)saved_line + change_col, (size_t)(cursor->col - change_col));
+        ins_bytes_len(saved_line + change_col, (size_t)(cursor->col - change_col));
       }
     }
 
@@ -4946,13 +4946,13 @@ static char_u *do_insert_char_pre(int c)
   textlock++;
   set_vim_var_string(VV_CHAR, buf, -1);
 
-  char_u *res = NULL;
+  char *res = NULL;
   if (ins_apply_autocmds(EVENT_INSERTCHARPRE)) {
     // Get the value of v:char.  It may be empty or more than one
     // character.  Only use it when changed, otherwise continue with the
     // original character to avoid breaking autoindent.
     if (STRCMP(buf, get_vim_var_str(VV_CHAR)) != 0) {
-      res = vim_strsave((char_u *)get_vim_var_str(VV_CHAR));
+      res = xstrdup(get_vim_var_str(VV_CHAR));
     }
   }
 
@@ -4962,7 +4962,7 @@ static char_u *do_insert_char_pre(int c)
   // Restore the State, it may have been changed.
   State = save_State;
 
-  return res;
+  return (char_u *)res;
 }
 
 bool get_can_cindent(void)
diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 06ee4c8d81..0c41381313 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -3909,7 +3909,7 @@ char *partial_name(partial_T *pt)
   FUNC_ATTR_PURE
 {
   if (pt->pt_name != NULL) {
-    return (char *)pt->pt_name;
+    return pt->pt_name;
   }
   return (char *)pt->pt_func->uf_name;
 }
@@ -3924,7 +3924,7 @@ static void partial_free(partial_T *pt)
   xfree(pt->pt_argv);
   tv_dict_unref(pt->pt_dict);
   if (pt->pt_name != NULL) {
-    func_unref(pt->pt_name);
+    func_unref((char_u *)pt->pt_name);
     xfree(pt->pt_name);
   } else {
     func_ptr_unref(pt->pt_func);
@@ -4478,7 +4478,7 @@ bool set_ref_in_item(typval_T *tv, int copyID, ht_stack_T **ht_stack, list_stack
 
     // A partial does not have a copyID, because it cannot contain itself.
     if (pt != NULL) {
-      abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
+      abort = set_ref_in_func((char_u *)pt->pt_name, pt->pt_func, copyID);
       if (pt->pt_dict != NULL) {
         typval_T dtv;
 
@@ -4846,7 +4846,7 @@ void filter_map(typval_T *argvars, typval_T *rettv, int map)
             break;
           }
 
-          vimvars[VV_KEY].vv_str = (char *)vim_strsave(di->di_key);
+          vimvars[VV_KEY].vv_str = xstrdup((char *)di->di_key);
           int r = filter_map_one(&di->di_tv, expr, map, &rem);
           tv_clear(&vimvars[VV_KEY].vv_tv);
           if (r == FAIL || did_emsg) {
@@ -5113,7 +5113,7 @@ void common_function(typval_T *argvars, typval_T *rettv, bool is_funcref)
         func_ptr_ref(pt->pt_func);
         xfree(name);
       } else {
-        pt->pt_name = (char_u *)name;
+        pt->pt_name = name;
         func_ref((char_u *)name);
       }
 
@@ -6208,7 +6208,7 @@ char *save_tv_as_string(typval_T *tv, ptrdiff_t *const len, bool endnl)
     buf_T *buf = buflist_findnr((int)tv->vval.v_number);
     if (buf) {
       for (linenr_T lnum = 1; lnum <= buf->b_ml.ml_line_count; lnum++) {
-        for (char *p = (char *)ml_get_buf(buf, lnum, false); *p != NUL; p++) {
+        for (char *p = ml_get_buf(buf, lnum, false); *p != NUL; p++) {
           *len += 1;
         }
         *len += 1;
@@ -6226,7 +6226,7 @@ char *save_tv_as_string(typval_T *tv, ptrdiff_t *const len, bool endnl)
     char *ret = xmalloc((size_t)(*len) + 1);
     char *end = ret;
     for (linenr_T lnum = 1; lnum <= buf->b_ml.ml_line_count; lnum++) {
-      for (char *p = (char *)ml_get_buf(buf, lnum, false); *p != NUL; p++) {
+      for (char *p = ml_get_buf(buf, lnum, false); *p != NUL; p++) {
         *end++ = (*p == '\n') ? NUL : *p;
       }
       *end++ = '\n';
@@ -6275,7 +6275,7 @@ int buf_byteidx_to_charidx(buf_T *buf, linenr_T lnum, int byteidx)
     lnum = buf->b_ml.ml_line_count;
   }
 
-  char *str = (char *)ml_get_buf(buf, lnum, false);
+  char *str = ml_get_buf(buf, lnum, false);
 
   if (*str == NUL) {
     return 0;
@@ -6313,7 +6313,7 @@ int buf_charidx_to_byteidx(buf_T *buf, linenr_T lnum, int charidx)
     lnum = buf->b_ml.ml_line_count;
   }
 
-  char *str = (char *)ml_get_buf(buf, lnum, false);
+  char *str = ml_get_buf(buf, lnum, false);
 
   // Convert the character offset to a byte offset
   char *t = str;
diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index 60a6ec6201..408b6e6cb5 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -849,7 +849,7 @@ static void get_col(typval_T *argvars, typval_T *rettv, bool charcol)
       // col(".") when the cursor is on the NUL at the end of the line
       // because of "coladd" can be seen as an extra column.
       if (virtual_active() && fp == &curwin->w_cursor) {
-        char *p = (char *)get_cursor_pos_ptr();
+        char *p = get_cursor_pos_ptr();
         if (curwin->w_cursor.coladd >=
             (colnr_T)win_chartabsize(curwin, p,
                                      curwin->w_virtcol - curwin->w_cursor.coladd)) {
@@ -930,12 +930,12 @@ static void f_chdir(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   // Return the current directory
-  char_u *cwd = xmalloc(MAXPATHL);
-  if (os_dirname(cwd, MAXPATHL) != FAIL) {
+  char *cwd = xmalloc(MAXPATHL);
+  if (os_dirname((char_u *)cwd, MAXPATHL) != FAIL) {
 #ifdef BACKSLASH_IN_FILENAME
     slash_adjust(cwd);
 #endif
-    rettv->vval.v_string = (char *)vim_strsave(cwd);
+    rettv->vval.v_string = xstrdup(cwd);
   }
   xfree(cwd);
 
@@ -2016,10 +2016,9 @@ static void f_expand(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
         options += WILD_ICASE;
       }
       if (rettv->v_type == VAR_STRING) {
-        rettv->vval.v_string = (char *)ExpandOne(&xpc, (char_u *)s, NULL, options,
-                                                 WILD_ALL);
+        rettv->vval.v_string = ExpandOne(&xpc, (char *)s, NULL, options, WILD_ALL);
       } else {
-        ExpandOne(&xpc, (char_u *)s, NULL, options, WILD_ALL_KEEP);
+        ExpandOne(&xpc, (char *)s, NULL, options, WILD_ALL_KEEP);
         tv_list_alloc_ret(rettv, xpc.xp_numfiles);
         for (int i = 0; i < xpc.xp_numfiles; i++) {
           tv_list_append_string(rettv->vval.v_list,
@@ -2437,7 +2436,7 @@ static void f_get(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
       pt = argvars[0].vval.v_partial;
     } else {
       CLEAR_FIELD(fref_pt);
-      fref_pt.pt_name = (char_u *)argvars[0].vval.v_string;
+      fref_pt.pt_name = argvars[0].vval.v_string;
       pt = &fref_pt;
     }
 
@@ -2579,9 +2578,8 @@ static void get_buffer_lines(buf_T *buf, linenr_T start, linenr_T end, int retli
     }
   } else {
     rettv->v_type = VAR_STRING;
-    rettv->vval.v_string =
-      (char *)((start >= 1 && start <= buf->b_ml.ml_line_count)
-               ? vim_strsave(ml_get_buf(buf, start, false)) : NULL);
+    rettv->vval.v_string = ((start >= 1 && start <= buf->b_ml.ml_line_count)
+                            ? xstrdup(ml_get_buf(buf, start, false)) : NULL);
   }
 }
 
@@ -2919,7 +2917,7 @@ static void f_getftime(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 /// "getftype({fname})" function
 static void f_getftype(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
-  char_u *type = NULL;
+  char *type = NULL;
   char *t;
 
   const char *fname = tv_get_string(&argvars[0]);
@@ -2945,9 +2943,9 @@ static void f_getftype(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
     } else {
       t = "other";
     }
-    type = vim_strsave((char_u *)t);
+    type = xstrdup(t);
   }
-  rettv->vval.v_string = (char *)type;
+  rettv->vval.v_string = type;
 }
 
 /// "getjumplist()" function
@@ -3441,11 +3439,11 @@ static void f_glob(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
       options += WILD_ICASE;
     }
     if (rettv->v_type == VAR_STRING) {
-      rettv->vval.v_string = (char *)ExpandOne(&xpc, (char_u *)
-                                               tv_get_string(&argvars[0]), NULL, options,
-                                               WILD_ALL);
+      rettv->vval.v_string = ExpandOne(&xpc, (char *)
+                                       tv_get_string(&argvars[0]), NULL, options,
+                                       WILD_ALL);
     } else {
-      ExpandOne(&xpc, (char_u *)tv_get_string(&argvars[0]), NULL, options,
+      ExpandOne(&xpc, (char *)tv_get_string(&argvars[0]), NULL, options,
                 WILD_ALL_KEEP);
       tv_list_alloc_ret(rettv, xpc.xp_numfiles);
       for (int i = 0; i < xpc.xp_numfiles; i++) {
@@ -5443,11 +5441,11 @@ static void f_pathshorten(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   }
 
   rettv->v_type = VAR_STRING;
-  const char_u *p = (char_u *)tv_get_string_chk(&argvars[0]);
+  const char *p = tv_get_string_chk(&argvars[0]);
   if (p == NULL) {
     rettv->vval.v_string = NULL;
   } else {
-    rettv->vval.v_string = (char *)vim_strsave(p);
+    rettv->vval.v_string = xstrdup(p);
     shorten_dir_len((char_u *)rettv->vval.v_string, trim_len);
   }
 }
@@ -5565,7 +5563,7 @@ static void f_prompt_getprompt(typval_T *argvars, typval_T *rettv, EvalFuncData
     return;
   }
 
-  rettv->vval.v_string = (char *)vim_strsave(buf_prompt_text(buf));
+  rettv->vval.v_string = xstrdup(buf_prompt_text(buf));
 }
 
 /// "prompt_setprompt({buffer}, {text})" function
@@ -7107,7 +7105,7 @@ static void f_screenstring(typval_T *argvars, typval_T *rettv, EvalFuncData fptr
     return;
   }
 
-  rettv->vval.v_string = (char *)vim_strsave(grid->chars[grid->line_offset[row] + (size_t)col]);
+  rettv->vval.v_string = xstrdup((char *)grid->chars[grid->line_offset[row] + (size_t)col]);
 }
 
 /// "search()" function
@@ -8052,7 +8050,7 @@ static void f_spellbadword(typval_T *argvars, typval_T *rettv, EvalFuncData fptr
     // Find the start and length of the badly spelled word.
     len = spell_move_to(curwin, FORWARD, true, true, &attr);
     if (len != 0) {
-      word = (char *)get_cursor_pos_ptr();
+      word = get_cursor_pos_ptr();
       curwin->w_set_curswant = true;
     }
   } else if (*curbuf->b_s.b_p_spl != NUL) {
@@ -8740,7 +8738,7 @@ static void f_swapname(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
       || buf->b_ml.ml_mfp->mf_fname == NULL) {
     rettv->vval.v_string = NULL;
   } else {
-    rettv->vval.v_string = (char *)vim_strsave(buf->b_ml.ml_mfp->mf_fname);
+    rettv->vval.v_string = xstrdup(buf->b_ml.ml_mfp->mf_fname);
   }
 }
 
@@ -9101,7 +9099,7 @@ static void f_taglist(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 static void f_tempname(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
   rettv->v_type = VAR_STRING;
-  rettv->vval.v_string = (char *)vim_tempname();
+  rettv->vval.v_string = vim_tempname();
 }
 
 /// "termopen(cmd[, cwd])" function
@@ -9595,12 +9593,12 @@ static void f_virtcol(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 /// "visualmode()" function
 static void f_visualmode(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
 {
-  char_u str[2];
+  char str[2];
 
   rettv->v_type = VAR_STRING;
-  str[0] = (char_u)curbuf->b_visual_mode_eval;
+  str[0] = (char)curbuf->b_visual_mode_eval;
   str[1] = NUL;
-  rettv->vval.v_string = (char *)vim_strsave(str);
+  rettv->vval.v_string = xstrdup(str);
 
   // A non-zero number or non-empty string argument: reset mode.
   if (non_zero_arg(&argvars[0])) {
diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index a409271596..f6b97fe05b 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -2777,7 +2777,7 @@ static void tv_dict_list(typval_T *const tv, typval_T *const rettv, const DictLi
     switch (what) {
       case kDictListKeys:
         tv_item.v_type = VAR_STRING;
-        tv_item.vval.v_string = (char *)vim_strsave(di->di_key);
+        tv_item.vval.v_string = xstrdup((char *)di->di_key);
         break;
       case kDictListValues:
         tv_copy(&di->di_tv, &tv_item);
diff --git a/src/nvim/eval/typval.h b/src/nvim/eval/typval.h
index 8177d01f90..cf7b04c8ce 100644
--- a/src/nvim/eval/typval.h
+++ b/src/nvim/eval/typval.h
@@ -360,15 +360,14 @@ struct ufunc {
 };
 
 struct partial_S {
-  int pt_refcount;  ///< Reference count.
-  char_u *pt_name;  ///< Function name; when NULL use pt_func->name.
-  ufunc_T *pt_func;  ///< Function pointer; when NULL lookup function with
-                     ///< pt_name.
-  bool pt_auto;  ///< When true the partial was created by using dict.member
-                 ///< in handle_subscript().
-  int pt_argc;  ///< Number of arguments.
+  int pt_refcount;    ///< Reference count.
+  char *pt_name;      ///< Function name; when NULL use pt_func->name.
+  ufunc_T *pt_func;   ///< Function pointer; when NULL lookup function with pt_name.
+  bool pt_auto;       ///< When true the partial was created by using dict.member
+                      ///< in handle_subscript().
+  int pt_argc;        ///< Number of arguments.
   typval_T *pt_argv;  ///< Arguments in allocated array.
-  dict_T *pt_dict;  ///< Dict for "self".
+  dict_T *pt_dict;    ///< Dict for "self".
 };
 
 /// Structure used for explicit stack while garbage collecting hash tables
diff --git a/src/nvim/eval/userfunc.c b/src/nvim/eval/userfunc.c
index 3ab66c319f..36bc51179c 100644
--- a/src/nvim/eval/userfunc.c
+++ b/src/nvim/eval/userfunc.c
@@ -142,18 +142,18 @@ static int get_function_args(char **argp, char_u endchar, garray_T *newargs, int
         any_default = true;
         p = skipwhite(p) + 1;
         p = skipwhite(p);
-        char_u *expr = (char_u *)p;
+        char *expr = p;
         if (eval1(&p, &rettv, false) != FAIL) {
           ga_grow(default_args, 1);
 
           // trim trailing whitespace
-          while (p > (char *)expr && ascii_iswhite(p[-1])) {
+          while (p > expr && ascii_iswhite(p[-1])) {
             p--;
           }
           c = (char_u)(*p);
           *p = NUL;
-          expr = vim_strsave(expr);
-          ((char **)(default_args->ga_data))[default_args->ga_len] = (char *)expr;
+          expr = xstrdup(expr);
+          ((char **)(default_args->ga_data))[default_args->ga_len] = expr;
           default_args->ga_len++;
           *p = (char)c;
         } else {
@@ -1680,7 +1680,7 @@ static void list_func_head(ufunc_T *fp, int indent, bool force)
 char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, partial_T **partial)
   FUNC_ATTR_NONNULL_ARG(1)
 {
-  char_u *name = NULL;
+  char *name = NULL;
   const char_u *start;
   const char_u *end;
   int lead;
@@ -1739,7 +1739,7 @@ char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, pa
       fdp->fd_di = lv.ll_di;
     }
     if (lv.ll_tv->v_type == VAR_FUNC && lv.ll_tv->vval.v_string != NULL) {
-      name = vim_strsave((char_u *)lv.ll_tv->vval.v_string);
+      name = xstrdup(lv.ll_tv->vval.v_string);
       *pp = (char *)end;
     } else if (lv.ll_tv->v_type == VAR_PARTIAL
                && lv.ll_tv->vval.v_partial != NULL) {
@@ -1753,7 +1753,7 @@ char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, pa
         memcpy(name, end + 1, (size_t)len);
         *pp = (char *)end + 1 + len;
       } else {
-        name = vim_strsave((char_u *)partial_name(lv.ll_tv->vval.v_partial));
+        name = xstrdup(partial_name(lv.ll_tv->vval.v_partial));
         *pp = (char *)end;
       }
       if (partial != NULL) {
@@ -1781,28 +1781,28 @@ char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, pa
   // Check if the name is a Funcref.  If so, use the value.
   if (lv.ll_exp_name != NULL) {
     len = (int)strlen(lv.ll_exp_name);
-    name = deref_func_name(lv.ll_exp_name, &len, partial,
-                           flags & TFN_NO_AUTOLOAD);
+    name = (char *)deref_func_name(lv.ll_exp_name, &len, partial,
+                                   flags & TFN_NO_AUTOLOAD);
     if ((const char *)name == lv.ll_exp_name) {
       name = NULL;
     }
   } else if (!(flags & TFN_NO_DEREF)) {
     len = (int)(end - (char_u *)(*pp));
-    name = deref_func_name((const char *)(*pp), &len, partial,
-                           flags & TFN_NO_AUTOLOAD);
-    if (name == (char_u *)(*pp)) {
+    name = (char *)deref_func_name((const char *)(*pp), &len, partial,
+                                   flags & TFN_NO_AUTOLOAD);
+    if (name == *pp) {
       name = NULL;
     }
   }
   if (name != NULL) {
-    name = vim_strsave(name);
+    name = xstrdup(name);
     *pp = (char *)end;
     if (STRNCMP(name, "<SNR>", 5) == 0) {
       // Change "<SNR>" to the byte sequence.
-      name[0] = K_SPECIAL;
-      name[1] = KS_EXTRA;
+      name[0] = (char)K_SPECIAL;
+      name[1] = (char)KS_EXTRA;
       name[2] = KE_SNR;
-      memmove(name + 3, name + 5, strlen((char *)name + 5) + 1);
+      memmove(name + 3, name + 5, strlen(name + 5) + 1);
     }
     goto theend;
   }
@@ -1865,8 +1865,8 @@ char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, pa
 
   name = xmalloc((size_t)len + (size_t)lead + 1);
   if (!skip && lead > 0) {
-    name[0] = K_SPECIAL;
-    name[1] = KS_EXTRA;
+    name[0] = (char)K_SPECIAL;
+    name[1] = (char)KS_EXTRA;
     name[2] = KE_SNR;
     if (sid_buf_len > 0) {  // If it's "<SID>"
       memcpy(name + 3, sid_buf, sid_buf_len);
@@ -1878,7 +1878,7 @@ char_u *trans_function_name(char **pp, bool skip, int flags, funcdict_T *fdp, pa
 
 theend:
   clear_lval(&lv);
-  return name;
+  return (char_u *)name;
 }
 
 #define MAX_FUNC_NESTING 50
@@ -3104,7 +3104,7 @@ char *get_return_cmd(void *rettv)
     STRCPY(IObuff + IOSIZE - 4, "...");
   }
   xfree(tofree);
-  return (char *)vim_strsave(IObuff);
+  return xstrdup((char *)IObuff);
 }
 
 /// Get next function line.
@@ -3192,7 +3192,7 @@ void make_partial(dict_T *const selfdict, typval_T *const rettv)
   } else {
     fname = rettv->v_type == VAR_FUNC || rettv->v_type == VAR_STRING
                                       ? (char_u *)rettv->vval.v_string
-                                      : rettv->vval.v_partial->pt_name;
+                                      : (char_u *)rettv->vval.v_partial->pt_name;
     // Translate "s:func" to the stored function name.
     fname = (char_u *)fname_trans_sid((char *)fname, (char *)fname_buf, (char **)&tofree, &error);
     fp = find_func(fname);
@@ -3208,7 +3208,7 @@ void make_partial(dict_T *const selfdict, typval_T *const rettv)
     pt->pt_auto = true;
     if (rettv->v_type == VAR_FUNC || rettv->v_type == VAR_STRING) {
       // Just a function: Take over the function name and use selfdict.
-      pt->pt_name = (char_u *)rettv->vval.v_string;
+      pt->pt_name = rettv->vval.v_string;
     } else {
       partial_T *ret_pt = rettv->vval.v_partial;
       int i;
@@ -3217,8 +3217,8 @@ void make_partial(dict_T *const selfdict, typval_T *const rettv)
       // args. Can't take over name or args, the partial might
       // be referenced elsewhere.
       if (ret_pt->pt_name != NULL) {
-        pt->pt_name = vim_strsave(ret_pt->pt_name);
-        func_ref(pt->pt_name);
+        pt->pt_name = xstrdup(ret_pt->pt_name);
+        func_ref((char_u *)pt->pt_name);
       } else {
         pt->pt_func = ret_pt->pt_func;
         func_ptr_ref(pt->pt_func);
diff --git a/src/nvim/ex_cmds.c b/src/nvim/ex_cmds.c
index 8f256728e3..12920d932d 100644
--- a/src/nvim/ex_cmds.c
+++ b/src/nvim/ex_cmds.c
@@ -118,7 +118,7 @@ void do_ascii(const exarg_T *const eap)
 {
   char *dig;
   int cc[MAX_MCO];
-  int c = utfc_ptr2char((char *)get_cursor_pos_ptr(), cc);
+  int c = utfc_ptr2char(get_cursor_pos_ptr(), cc);
   if (c == NUL) {
     msg("NUL");
     return;
@@ -1068,7 +1068,7 @@ void ex_copy(linenr_T line1, linenr_T line2, linenr_T n)
 
   curwin->w_cursor.lnum = n;
   while (line1 <= line2) {
-    // need to use vim_strsave() because the line will be unlocked within
+    // need to use xstrdup() because the line will be unlocked within
     // ml_append()
     p = xstrdup(ml_get(line1));
     ml_append(curwin->w_cursor.lnum, p, (colnr_T)0, false);
@@ -1305,8 +1305,8 @@ static void do_filter(linenr_T line1, linenr_T line2, exarg_T *eap, char *cmd, b
     curbuf->b_op_start.lnum = line1;
     curbuf->b_op_end.lnum = line2;
     curwin->w_cursor.lnum = line2;
-  } else if ((do_in && (itmp = (char *)vim_tempname()) == NULL)
-             || (do_out && (otmp = (char *)vim_tempname()) == NULL)) {
+  } else if ((do_in && (itmp = vim_tempname()) == NULL)
+             || (do_out && (otmp = vim_tempname()) == NULL)) {
     emsg(_(e_notmp));
     goto filterend;
   }
@@ -3291,7 +3291,7 @@ static bool sub_joining_lines(exarg_T *eap, char *pat, char *sub, char *cmd, boo
 
     if (save) {
       if ((cmdmod.cmod_flags & CMOD_KEEPPATTERNS) == 0) {
-        save_re_pat(RE_SUBST, (char_u *)pat, p_magic);
+        save_re_pat(RE_SUBST, pat, p_magic);
       }
       // put pattern in history
       add_to_history(HIST_SEARCH, pat, true, NUL);
@@ -3608,7 +3608,7 @@ static int do_sub(exarg_T *eap, proftime_T timeout, long cmdpreview_ns, handle_T
     sub = xstrdup(sub);
     sub_copy = sub;
   } else {
-    char *newsub = (char *)regtilde((char_u *)sub, p_magic, cmdpreview);
+    char *newsub = regtilde(sub, p_magic, cmdpreview);
     if (newsub != sub) {
       // newsub was allocated, free it later.
       sub_copy = newsub;
@@ -4782,7 +4782,7 @@ static int show_sub(exarg_T *eap, pos_T old_cusr, PreviewLines *preview_lines, i
         if (next_linenr == orig_buf->b_ml.ml_line_count + 1) {
           line = "";
         } else {
-          line = (char *)ml_get_buf(orig_buf, next_linenr, false);
+          line = ml_get_buf(orig_buf, next_linenr, false);
           line_size = strlen(line) + (size_t)col_width + 1;
 
           // Reallocate if line not long enough
diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index 8fb166d2c9..e32eb860ce 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -785,7 +785,7 @@ int do_cmdline(char *cmdline, LineGetter fgetline, void *cookie, int flags)
         vim_snprintf((char *)IObuff, IOSIZE,
                      _("E605: Exception not caught: %s"),
                      current_exception->value);
-        p = (char *)vim_strsave(IObuff);
+        p = xstrdup((char *)IObuff);
         break;
       case ET_ERROR:
         messages = current_exception->messages;
@@ -1300,7 +1300,7 @@ static void parse_register(exarg_T *eap)
       // for '=' register: accept the rest of the line as an expression
       if (eap->arg[-1] == '=' && eap->arg[0] != NUL) {
         if (!eap->skip) {
-          set_expr_line(vim_strsave((char_u *)eap->arg));
+          set_expr_line(xstrdup(eap->arg));
         }
         eap->arg += STRLEN(eap->arg);
       }
@@ -3829,7 +3829,7 @@ int expand_filename(exarg_T *eap, char **cmdlinep, char **errormsgp)
       if (p_wic) {
         options += WILD_ICASE;
       }
-      p = (char *)ExpandOne(&xpc, (char_u *)eap->arg, NULL, options, WILD_EXPAND_FREE);
+      p = ExpandOne(&xpc, eap->arg, NULL, options, WILD_EXPAND_FREE);
       if (p == NULL) {
         return FAIL;
       }
@@ -5274,7 +5274,7 @@ static void ex_swapname(exarg_T *eap)
   if (curbuf->b_ml.ml_mfp == NULL || curbuf->b_ml.ml_mfp->mf_fname == NULL) {
     msg(_("No swap file"));
   } else {
-    msg((char *)curbuf->b_ml.ml_mfp->mf_fname);
+    msg(curbuf->b_ml.ml_mfp->mf_fname);
   }
 }
 
@@ -6563,7 +6563,7 @@ static void ex_tag_cmd(exarg_T *eap, char *name)
     cmd = DT_LTAG;
   }
 
-  do_tag((char_u *)eap->arg, cmd, eap->addr_count > 0 ? (int)eap->line2 : 1,
+  do_tag(eap->arg, cmd, eap->addr_count > 0 ? (int)eap->line2 : 1,
          eap->forceit, true);
 }
 
diff --git a/src/nvim/ex_eval.c b/src/nvim/ex_eval.c
index 20725b81ee..f40149d07a 100644
--- a/src/nvim/ex_eval.c
+++ b/src/nvim/ex_eval.c
@@ -529,7 +529,7 @@ static void discard_exception(except_T *excp, bool was_finished)
   if (p_verbose >= 13 || debug_break_level > 0) {
     int save_msg_silent = msg_silent;
 
-    saved_IObuff = (char *)vim_strsave(IObuff);
+    saved_IObuff = xstrdup((char *)IObuff);
     if (debug_break_level > 0) {
       msg_silent = false;               // display messages
     } else {
diff --git a/src/nvim/ex_getln.c b/src/nvim/ex_getln.c
index da99a03c38..cf95287d61 100644
--- a/src/nvim/ex_getln.c
+++ b/src/nvim/ex_getln.c
@@ -105,7 +105,7 @@ typedef struct command_line_state {
   int c;
   int gotesc;                           // true when <ESC> just typed
   int do_abbr;                          // when true check for abbr.
-  char_u *lookfor;                      // string to match
+  char *lookfor;                        // string to match
   int hiscnt;                           // current history line in use
   int save_hiscnt;                      // history line before attempting
                                         // to jump to next match
@@ -116,7 +116,7 @@ typedef struct command_line_state {
   int res;
   int save_msg_scroll;
   int save_State;                 // remember State when called
-  char_u *save_p_icm;
+  char *save_p_icm;
   int some_key_typed;                   // one of the keys was typed
   // mouse drag and release events are ignored, unless they are
   // preceded with a mouse down event
@@ -632,7 +632,7 @@ static uint8_t *command_line_enter(int firstc, long count, int indent, bool init
     .ignore_drag_release = true,
   };
   CommandLineState *s = &state;
-  s->save_p_icm = vim_strsave((char_u *)p_icm);
+  s->save_p_icm = xstrdup(p_icm);
   init_incsearch_state(&s->is_state);
   CmdlineInfo save_ccline;
   bool did_save_ccline = false;
@@ -879,7 +879,7 @@ static uint8_t *command_line_enter(int firstc, long count, int indent, bool init
     need_wait_return = false;
   }
 
-  set_string_option_direct("icm", -1, (char *)s->save_p_icm, OPT_FREE, SID_NONE);
+  set_string_option_direct("icm", -1, s->save_p_icm, OPT_FREE, SID_NONE);
   State = s->save_State;
   if (cmdpreview != save_cmdpreview) {
     cmdpreview = save_cmdpreview;  // restore preview state
@@ -1087,7 +1087,7 @@ static int command_line_execute(VimState *state, int key)
       s->c = get_expr_register();
       if (s->c == '=') {
         textlock++;
-        p = get_expr_line();
+        p = (char_u *)get_expr_line();
         textlock--;
 
         if (p != NULL) {
@@ -1853,7 +1853,7 @@ static int command_line_handle_key(CommandLineState *s)
 
     // save current command string so it can be restored later
     if (s->lookfor == NULL) {
-      s->lookfor = vim_strsave((char_u *)ccline.cmdbuff);
+      s->lookfor = xstrdup(ccline.cmdbuff);
       s->lookfor[ccline.cmdpos] = NUL;
     }
 
@@ -1870,13 +1870,13 @@ static int command_line_handle_key(CommandLineState *s)
       XFREE_CLEAR(ccline.cmdbuff);
       s->xpc.xp_context = EXPAND_NOTHING;
       if (s->hiscnt == get_hislen()) {
-        p = s->lookfor;                  // back to the old one
+        p = (char_u *)s->lookfor;                  // back to the old one
       } else {
         p = (char_u *)get_histentry(s->histype)[s->hiscnt].hisstr;
       }
 
       if (s->histype == HIST_SEARCH
-          && p != s->lookfor
+          && p != (char_u *)s->lookfor
           && (old_firstc = p[STRLEN(p) + 1]) != s->firstc) {
         // Correct for the separator character used when
         // adding the history entry vs the one used now.
diff --git a/src/nvim/file_search.c b/src/nvim/file_search.c
index 76a429b5ef..5416be651d 100644
--- a/src/nvim/file_search.c
+++ b/src/nvim/file_search.c
@@ -69,7 +69,7 @@
 #include "nvim/vim.h"
 #include "nvim/window.h"
 
-static char_u *ff_expand_buffer = NULL;  // used for expanding filenames
+static char *ff_expand_buffer = NULL;  // used for expanding filenames
 
 // type for the directory search stack
 typedef struct ff_stack {
@@ -105,7 +105,7 @@ typedef struct ff_visited {
 
   // Visited directories are different if the wildcard string are
   // different. So we have to save it.
-  char_u *ffv_wc_path;
+  char *ffv_wc_path;
 
   // use FileID for comparison (needed because of links), else use filename.
   bool file_id_valid;
@@ -131,7 +131,7 @@ typedef struct ff_visited_list_hdr {
   struct ff_visited_list_hdr *ffvl_next;
 
   // the filename the attached visited list is for
-  char_u *ffvl_filename;
+  char *ffvl_filename;
 
   ff_visited_T *ffvl_visited_list;
 } ff_visited_list_hdr_T;
@@ -259,12 +259,12 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
     // Reuse old visited lists. Get the visited list for the given
     // filename. If no list for the current filename exists, creates a new
     // one.
-    search_ctx->ffsc_visited_list = ff_get_visited_list((char_u *)filename,
+    search_ctx->ffsc_visited_list = ff_get_visited_list(filename,
                                                         &search_ctx->ffsc_visited_lists_list);
     if (search_ctx->ffsc_visited_list == NULL) {
       goto error_return;
     }
-    search_ctx->ffsc_dir_visited_list = ff_get_visited_list((char_u *)filename,
+    search_ctx->ffsc_dir_visited_list = ff_get_visited_list(filename,
                                                             &search_ctx->ffsc_dir_visited_lists_list);
     if (search_ctx->ffsc_dir_visited_list == NULL) {
       goto error_return;
@@ -286,7 +286,7 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
     if (!vim_isAbsName((char_u *)rel_fname) && len + 1 < MAXPATHL) {
       // Make the start dir an absolute path name.
       STRLCPY(ff_expand_buffer, rel_fname, len + 1);
-      search_ctx->ffsc_start_dir = FullName_save((char *)ff_expand_buffer, false);
+      search_ctx->ffsc_start_dir = FullName_save(ff_expand_buffer, false);
     } else {
       search_ctx->ffsc_start_dir = xstrnsave(rel_fname, len);
     }
@@ -310,11 +310,11 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
       path += 2;
     } else
 #endif
-    if (os_dirname(ff_expand_buffer, MAXPATHL) == FAIL) {
+    if (os_dirname((char_u *)ff_expand_buffer, MAXPATHL) == FAIL) {
       goto error_return;
     }
 
-    search_ctx->ffsc_start_dir = (char *)vim_strsave(ff_expand_buffer);
+    search_ctx->ffsc_start_dir = xstrdup(ff_expand_buffer);
 
 #ifdef BACKSLASH_IN_FILENAME
     // A path that starts with "/dir" is relative to the drive, not to the
@@ -396,12 +396,12 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
         break;
       }
       if (STRNCMP(wc_part, "**", 2) == 0) {
-        ff_expand_buffer[len++] = (char_u)(*wc_part++);
-        ff_expand_buffer[len++] = (char_u)(*wc_part++);
+        ff_expand_buffer[len++] = *wc_part++;
+        ff_expand_buffer[len++] = *wc_part++;
 
         llevel = strtol(wc_part, &errpt, 10);
         if (errpt != wc_part && llevel > 0 && llevel < 255) {
-          ff_expand_buffer[len++] = (char_u)llevel;
+          ff_expand_buffer[len++] = (char)llevel;
         } else if (errpt != wc_part && llevel == 0) {
           // restrict is 0 -> remove already added '**'
           len -= 2;
@@ -416,11 +416,11 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
           goto error_return;
         }
       } else {
-        ff_expand_buffer[len++] = (char_u)(*wc_part++);
+        ff_expand_buffer[len++] = *wc_part++;
       }
     }
     ff_expand_buffer[len] = NUL;
-    search_ctx->ffsc_wc_path = (char *)vim_strsave(ff_expand_buffer);
+    search_ctx->ffsc_wc_path = xstrdup(ff_expand_buffer);
   } else {
     search_ctx->ffsc_fix_path = xstrdup(path);
   }
@@ -439,7 +439,7 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
     goto error_return;
   }
   STRCPY(ff_expand_buffer, search_ctx->ffsc_start_dir);
-  add_pathsep((char *)ff_expand_buffer);
+  add_pathsep(ff_expand_buffer);
   {
     size_t eb_len = STRLEN(ff_expand_buffer);
     char_u *buf = xmalloc(eb_len + STRLEN(search_ctx->ffsc_fix_path) + 1);
@@ -448,7 +448,7 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
     STRCPY(buf + eb_len, search_ctx->ffsc_fix_path);
     if (os_isdir((char *)buf)) {
       STRCAT(ff_expand_buffer, search_ctx->ffsc_fix_path);
-      add_pathsep((char *)ff_expand_buffer);
+      add_pathsep(ff_expand_buffer);
     } else {
       char *p = path_tail(search_ctx->ffsc_fix_path);
       char *wc_path = NULL;
@@ -464,7 +464,7 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
           goto error_return;
         }
         STRLCAT(ff_expand_buffer, search_ctx->ffsc_fix_path, eb_len + (size_t)len + 1);
-        add_pathsep((char *)ff_expand_buffer);
+        add_pathsep(ff_expand_buffer);
       } else {
         len = (int)STRLEN(search_ctx->ffsc_fix_path);
       }
@@ -484,7 +484,7 @@ void *vim_findfile_init(char *path, char *filename, char *stopdirs, int level, i
     xfree(buf);
   }
 
-  sptr = ff_create_stack_element(ff_expand_buffer, (char_u *)search_ctx->ffsc_wc_path, level, 0);
+  sptr = ff_create_stack_element(ff_expand_buffer, search_ctx->ffsc_wc_path, level, 0);
 
   ff_push(search_ctx, sptr);
   search_ctx->ffsc_file_to_search = xstrdup(filename);
@@ -607,7 +607,7 @@ char_u *vim_findfile(void *search_ctx_arg)
       // first time (hence stackp->ff_filearray == NULL)
       if (stackp->ffs_filearray == NULL
           && ff_check_visited(&search_ctx->ffsc_dir_visited_list->ffvl_visited_list,
-                              stackp->ffs_fix_path, stackp->ffs_wc_path) == FAIL) {
+                              (char *)stackp->ffs_fix_path, (char *)stackp->ffs_wc_path) == FAIL) {
 #ifdef FF_VERBOSE
         if (p_verbose >= 5) {
           verbose_enter_scroll();
@@ -787,7 +787,7 @@ char_u *vim_findfile(void *search_ctx_arg)
                                == os_isdir((char *)file_path)))))
 #ifndef FF_VERBOSE
                   && (ff_check_visited(&search_ctx->ffsc_visited_list->ffvl_visited_list,
-                                       file_path, (char_u *)"") == OK)
+                                       (char *)file_path, "") == OK)
 #endif
                   ) {
 #ifdef FF_VERBOSE
@@ -811,10 +811,10 @@ char_u *vim_findfile(void *search_ctx_arg)
                 if (!path_with_url((char *)file_path)) {
                   simplify_filename(file_path);
                 }
-                if (os_dirname(ff_expand_buffer, MAXPATHL)
+                if (os_dirname((char_u *)ff_expand_buffer, MAXPATHL)
                     == OK) {
                   p = path_shorten_fname(file_path,
-                                         ff_expand_buffer);
+                                         (char_u *)ff_expand_buffer);
                   if (p != NULL) {
                     STRMOVE(file_path, p);
                   }
@@ -845,8 +845,8 @@ char_u *vim_findfile(void *search_ctx_arg)
               continue;                 // not a directory
             }
             ff_push(search_ctx,
-                    ff_create_stack_element((char_u *)stackp->ffs_filearray[i],
-                                            rest_of_wildcards,
+                    ff_create_stack_element(stackp->ffs_filearray[i],
+                                            (char *)rest_of_wildcards,
                                             stackp->ffs_level - 1, 0));
           }
         }
@@ -867,8 +867,8 @@ char_u *vim_findfile(void *search_ctx_arg)
             continue;               // not a directory
           }
           ff_push(search_ctx,
-                  ff_create_stack_element((char_u *)stackp->ffs_filearray[i],
-                                          stackp->ffs_wc_path, stackp->ffs_level - 1, 1));
+                  ff_create_stack_element(stackp->ffs_filearray[i],
+                                          (char *)stackp->ffs_wc_path, stackp->ffs_level - 1, 1));
         }
       }
 
@@ -914,8 +914,8 @@ char_u *vim_findfile(void *search_ctx_arg)
       STRCAT(file_path, search_ctx->ffsc_fix_path);
 
       // create a new stack entry
-      sptr = ff_create_stack_element(file_path,
-                                     (char_u *)search_ctx->ffsc_wc_path, search_ctx->ffsc_level, 0);
+      sptr = ff_create_stack_element((char *)file_path,
+                                     search_ctx->ffsc_wc_path, search_ctx->ffsc_level, 0);
       ff_push(search_ctx, sptr);
     } else {
       break;
@@ -972,7 +972,7 @@ static void ff_free_visited_list(ff_visited_T *vl)
 
 /// @return  the already visited list for the given filename. If none is found it
 ///          allocates a new one.
-static ff_visited_list_hdr_T *ff_get_visited_list(char_u *filename,
+static ff_visited_list_hdr_T *ff_get_visited_list(char *filename,
                                                   ff_visited_list_hdr_T **list_headp)
 {
   ff_visited_list_hdr_T *retptr = NULL;
@@ -1009,7 +1009,7 @@ static ff_visited_list_hdr_T *ff_get_visited_list(char_u *filename,
   retptr = xmalloc(sizeof(*retptr));
 
   retptr->ffvl_visited_list = NULL;
-  retptr->ffvl_filename = vim_strsave(filename);
+  retptr->ffvl_filename = xstrdup(filename);
   retptr->ffvl_next = *list_headp;
   *list_headp = retptr;
 
@@ -1060,7 +1060,7 @@ static bool ff_wc_equal(char_u *s1, char_u *s2)
 ///
 /// @return  FAIL if the given file/dir is already in the list or,
 ///          OK if it is newly added
-static int ff_check_visited(ff_visited_T **visited_list, char_u *fname, char_u *wc_path)
+static int ff_check_visited(ff_visited_T **visited_list, char *fname, char *wc_path)
 {
   ff_visited_T *vp;
   bool url = false;
@@ -1068,12 +1068,12 @@ static int ff_check_visited(ff_visited_T **visited_list, char_u *fname, char_u *
   FileID file_id;
   // For a URL we only compare the name, otherwise we compare the
   // device/inode.
-  if (path_with_url((char *)fname)) {
+  if (path_with_url(fname)) {
     STRLCPY(ff_expand_buffer, fname, MAXPATHL);
     url = true;
   } else {
     ff_expand_buffer[0] = NUL;
-    if (!os_fileid((char *)fname, &file_id)) {
+    if (!os_fileid(fname, &file_id)) {
       return FAIL;
     }
   }
@@ -1084,7 +1084,7 @@ static int ff_check_visited(ff_visited_T **visited_list, char_u *fname, char_u *
         || (!url && vp->file_id_valid
             && os_fileid_equal(&(vp->file_id), &file_id))) {
       // are the wildcard parts equal
-      if (ff_wc_equal(vp->ffv_wc_path, wc_path)) {
+      if (ff_wc_equal((char_u *)vp->ffv_wc_path, (char_u *)wc_path)) {
         // already visited
         return FAIL;
       }
@@ -1104,7 +1104,7 @@ static int ff_check_visited(ff_visited_T **visited_list, char_u *fname, char_u *
   }
 
   if (wc_path != NULL) {
-    vp->ffv_wc_path = vim_strsave(wc_path);
+    vp->ffv_wc_path = xstrdup(wc_path);
   } else {
     vp->ffv_wc_path = NULL;
   }
@@ -1116,7 +1116,7 @@ static int ff_check_visited(ff_visited_T **visited_list, char_u *fname, char_u *
 }
 
 /// create stack element from given path pieces
-static ff_stack_T *ff_create_stack_element(char_u *fix_part, char_u *wc_part, int level,
+static ff_stack_T *ff_create_stack_element(char *fix_part, char *wc_part, int level,
                                            int star_star_empty)
 {
   ff_stack_T *new = xmalloc(sizeof(ff_stack_T));
@@ -1131,14 +1131,14 @@ static ff_stack_T *ff_create_stack_element(char_u *fix_part, char_u *wc_part, in
 
   // the following saves NULL pointer checks in vim_findfile
   if (fix_part == NULL) {
-    fix_part = (char_u *)"";
+    fix_part = "";
   }
-  new->ffs_fix_path = vim_strsave(fix_part);
+  new->ffs_fix_path = (char_u *)xstrdup(fix_part);
 
   if (wc_part == NULL) {
-    wc_part  = (char_u *)"";
+    wc_part = "";
   }
-  new->ffs_wc_path = vim_strsave(wc_part);
+  new->ffs_wc_path = (char_u *)xstrdup(wc_part);
 
   return new;
 }
@@ -1292,7 +1292,7 @@ char_u *find_file_in_path(char_u *ptr, size_t len, int options, int first, char_
                                   FINDFILE_BOTH, rel_fname, (char_u *)curbuf->b_p_sua);
 }
 
-static char_u *ff_file_to_find = NULL;
+static char *ff_file_to_find = NULL;
 static void *fdip_search_ctx = NULL;
 
 #if defined(EXITFREE)
@@ -1338,7 +1338,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
   static char *dir;
   static int did_findfile_init = false;
   char_u save_char;
-  char_u *file_name = NULL;
+  char *file_name = NULL;
   char *buf = NULL;
   int rel_to_curdir;
 
@@ -1359,10 +1359,10 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
     ptr[len] = save_char;
 
     xfree(ff_file_to_find);
-    ff_file_to_find = vim_strsave((char_u *)NameBuff);
+    ff_file_to_find = xstrdup(NameBuff);
     if (options & FNAME_UNESC) {
       // Change all "\ " to " ".
-      for (ptr = ff_file_to_find; *ptr != NUL; ptr++) {
+      for (ptr = (char_u *)ff_file_to_find; *ptr != NUL; ptr++) {
         if (ptr[0] == '\\' && ptr[1] == ' ') {
           memmove(ptr, ptr + 1, STRLEN(ptr));
         }
@@ -1376,7 +1376,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
                        || (ff_file_to_find[1] == '.'
                            && (ff_file_to_find[2] == NUL
                                || vim_ispathsep(ff_file_to_find[2])))));
-  if (vim_isAbsName(ff_file_to_find)
+  if (vim_isAbsName((char_u *)ff_file_to_find)
       // "..", "../path", "." and "./path": don't use the path_option
       || rel_to_curdir
 #if defined(WIN32)
@@ -1390,8 +1390,8 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
     // If this is not a first call, return NULL.  We already returned a
     // filename on the first call.
     if (first == true) {
-      if (path_with_url((char *)ff_file_to_find)) {
-        file_name = vim_strsave(ff_file_to_find);
+      if (path_with_url(ff_file_to_find)) {
+        file_name = xstrdup(ff_file_to_find);
         goto theend;
       }
 
@@ -1420,7 +1420,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
                && (find_what == FINDFILE_BOTH
                    || ((find_what == FINDFILE_DIR)
                        == os_isdir(NameBuff))))) {
-            file_name = vim_strsave((char_u *)NameBuff);
+            file_name = xstrdup(NameBuff);
             goto theend;
           }
           if (*buf == NUL) {
@@ -1444,7 +1444,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
 
     for (;;) {
       if (did_findfile_init) {
-        file_name = vim_findfile(fdip_search_ctx);
+        file_name = (char *)vim_findfile(fdip_search_ctx);
         if (file_name != NULL) {
           break;
         }
@@ -1468,7 +1468,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
 
         // get the stopdir string
         r_ptr = vim_findfile_stopdir((char_u *)buf);
-        fdip_search_ctx = vim_findfile_init(buf, (char *)ff_file_to_find,
+        fdip_search_ctx = vim_findfile_init(buf, ff_file_to_find,
                                             (char *)r_ptr, 100, false, find_what,
                                             fdip_search_ctx, false, (char *)rel_fname);
         if (fdip_search_ctx != NULL) {
@@ -1499,7 +1499,7 @@ char_u *find_file_in_path_option(char_u *ptr, size_t len, int options, int first
   }
 
 theend:
-  return file_name;
+  return (char_u *)file_name;
 }
 
 void do_autocmd_dirchanged(char *new_dir, CdScope scope, CdCause cause, bool pre)
diff --git a/src/nvim/fileio.c b/src/nvim/fileio.c
index b399885095..0d8eec1023 100644
--- a/src/nvim/fileio.c
+++ b/src/nvim/fileio.c
@@ -2049,7 +2049,7 @@ static char_u *readfile_charconvert(char_u *fname, char_u *fenc, int *fdp)
   char_u *tmpname;
   char *errmsg = NULL;
 
-  tmpname = vim_tempname();
+  tmpname = (char_u *)vim_tempname();
   if (tmpname == NULL) {
     errmsg = _("Can't find temp file for conversion");
   } else {
@@ -2697,7 +2697,7 @@ int buf_write(buf_T *buf, char *fname, char *sfname, linenr_T start, linenr_T en
           }
         }
 
-        rootname = (char *)get_file_in_dir((char_u *)fname, IObuff);
+        rootname = get_file_in_dir(fname, (char *)IObuff);
         if (rootname == NULL) {
           some_error = true;                // out of memory
           goto nobackup;
@@ -2847,7 +2847,7 @@ nobackup:
         }
 
         if (backup == NULL) {
-          rootname = (char *)get_file_in_dir((char_u *)fname, IObuff);
+          rootname = get_file_in_dir(fname, (char *)IObuff);
           if (rootname == NULL) {
             backup = NULL;
           } else {
@@ -2993,7 +2993,7 @@ nobackup:
     // writing, write to a temp file instead and let the conversion
     // overwrite the original file.
     if (*p_ccv != NUL) {
-      wfname = (char *)vim_tempname();
+      wfname = vim_tempname();
       if (wfname == NULL) {  // Can't write without a tempfile!
         SET_ERRMSG(_("E214: Can't find temp file for writing"));
         goto restore_backup;
@@ -3170,7 +3170,7 @@ restore_backup:
     for (lnum = start; lnum <= end; lnum++) {
       // The next while loop is done once for each character written.
       // Keep it fast!
-      ptr = (char *)ml_get_buf(buf, lnum, false) - 1;
+      ptr = ml_get_buf(buf, lnum, false) - 1;
       if (write_undo_file) {
         sha256_update(&sha_ctx, (char_u *)ptr + 1, (uint32_t)(STRLEN(ptr + 1) + 1));
       }
@@ -4704,13 +4704,13 @@ static int move_lines(buf_T *frombuf, buf_T *tobuf)
   buf_T *tbuf = curbuf;
   int retval = OK;
   linenr_T lnum;
-  char_u *p;
+  char *p;
 
   // Copy the lines in "frombuf" to "tobuf".
   curbuf = tobuf;
   for (lnum = 1; lnum <= frombuf->b_ml.ml_line_count; lnum++) {
-    p = vim_strsave(ml_get_buf(frombuf, lnum, false));
-    if (ml_append(lnum - 1, (char *)p, 0, false) == FAIL) {
+    p = xstrdup(ml_get_buf(frombuf, lnum, false));
+    if (ml_append(lnum - 1, p, 0, false) == FAIL) {
       xfree(p);
       retval = FAIL;
       break;
@@ -5358,7 +5358,7 @@ static bool vim_settempdir(char *tempdir)
 ///
 /// @return  pointer to the temp file name or NULL if Nvim can't create
 ///          temporary directory for its own temporary files.
-char_u *vim_tempname(void)
+char *vim_tempname(void)
 {
   // Temp filename counter.
   static uint64_t temp_count;
@@ -5370,10 +5370,10 @@ char_u *vim_tempname(void)
 
   // There is no need to check if the file exists, because we own the directory
   // and nobody else creates a file in it.
-  char_u template[TEMP_FILE_PATH_MAXLEN];
-  snprintf((char *)template, TEMP_FILE_PATH_MAXLEN,
+  char template[TEMP_FILE_PATH_MAXLEN];
+  snprintf(template, TEMP_FILE_PATH_MAXLEN,
            "%s%" PRIu64, tempdir, temp_count++);
-  return vim_strsave(template);
+  return xstrdup(template);
 }
 
 /// Tries matching a filename with a "pattern" ("prog" is NULL), or use the
diff --git a/src/nvim/fold.c b/src/nvim/fold.c
index 0f085df3d0..2e8d282ede 100644
--- a/src/nvim/fold.c
+++ b/src/nvim/fold.c
@@ -1582,7 +1582,7 @@ static void foldAddMarker(buf_T *buf, pos_T pos, const char *marker, size_t mark
   linenr_T lnum = pos.lnum;
 
   // Allocate a new line: old-line + 'cms'-start + marker + 'cms'-end
-  char *line = (char *)ml_get_buf(buf, lnum, false);
+  char *line = ml_get_buf(buf, lnum, false);
   size_t line_len = STRLEN(line);
   size_t added = 0;
 
@@ -1640,7 +1640,7 @@ static void foldDelMarker(buf_T *buf, linenr_T lnum, char *marker, size_t marker
   }
 
   char *cms = buf->b_p_cms;
-  char *line = (char *)ml_get_buf(buf, lnum, false);
+  char *line = ml_get_buf(buf, lnum, false);
   for (char *p = line; *p != NUL; p++) {
     if (STRNCMP(p, marker, markerlen) != 0) {
       continue;
@@ -2848,7 +2848,7 @@ static void foldlevelIndent(fline_T *flp)
   linenr_T lnum = flp->lnum + flp->off;
 
   buf_T *buf = flp->wp->w_buffer;
-  char *s = skipwhite((char *)ml_get_buf(buf, lnum, false));
+  char *s = skipwhite(ml_get_buf(buf, lnum, false));
 
   // empty line or lines starting with a character in 'foldignore': level
   // depends on surrounding lines
@@ -3010,7 +3010,7 @@ static void foldlevelMarker(fline_T *flp)
   flp->start = 0;
   flp->lvl_next = flp->lvl;
 
-  char *s = (char *)ml_get_buf(flp->wp->w_buffer, flp->lnum + flp->off, false);
+  char *s = ml_get_buf(flp->wp->w_buffer, flp->lnum + flp->off, false);
   while (*s) {
     if (*s == cstart
         && STRNCMP(s + 1, startmarker, foldstartmarkerlen - 1) == 0) {
diff --git a/src/nvim/getchar.c b/src/nvim/getchar.c
index e125d88395..0f0e3aece1 100644
--- a/src/nvim/getchar.c
+++ b/src/nvim/getchar.c
@@ -1708,26 +1708,26 @@ static void getchar_common(typval_T *argvars, typval_T *rettv)
 
   rettv->vval.v_number = n;
   if (n != 0 && (IS_SPECIAL(n) || mod_mask != 0)) {
-    char_u temp[10];                // modifier: 3, mbyte-char: 6, NUL: 1
+    char temp[10];                // modifier: 3, mbyte-char: 6, NUL: 1
     int i = 0;
 
     // Turn a special key into three bytes, plus modifier.
     if (mod_mask != 0) {
-      temp[i++] = K_SPECIAL;
-      temp[i++] = KS_MODIFIER;
-      temp[i++] = (char_u)mod_mask;
+      temp[i++] = (char)K_SPECIAL;
+      temp[i++] = (char)KS_MODIFIER;
+      temp[i++] = (char)mod_mask;
     }
     if (IS_SPECIAL(n)) {
-      temp[i++] = K_SPECIAL;
-      temp[i++] = (char_u)K_SECOND(n);
-      temp[i++] = K_THIRD(n);
+      temp[i++] = (char)K_SPECIAL;
+      temp[i++] = (char)K_SECOND(n);
+      temp[i++] = (char)K_THIRD(n);
     } else {
-      i += utf_char2bytes((int)n, (char *)temp + i);
+      i += utf_char2bytes((int)n, temp + i);
     }
     assert(i < 10);
     temp[i++] = NUL;
     rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = (char *)vim_strsave(temp);
+    rettv->vval.v_string = xstrdup(temp);
 
     if (is_mouse_key((int)n)) {
       int row = mouse_row;
@@ -2135,7 +2135,7 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
 
   // complete match
   if (keylen >= 0 && keylen <= typebuf.tb_len) {
-    char_u *map_str = NULL;
+    char *map_str = NULL;
 
     // Write chars to script file(s).
     // Note: :lmap mappings are written *after* being applied. #5658
@@ -2175,8 +2175,8 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
     char save_m_expr = mp->m_expr;
     int save_m_noremap = mp->m_noremap;
     char save_m_silent = mp->m_silent;
-    char_u *save_m_keys = NULL;  // only saved when needed
-    char_u *save_m_str = NULL;  // only saved when needed
+    char *save_m_keys = NULL;  // only saved when needed
+    char *save_m_str = NULL;  // only saved when needed
     LuaRef save_m_luaref = mp->m_luaref;
 
     // Handle ":map <expr>": evaluate the {rhs} as an
@@ -2193,9 +2193,9 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
       vgetc_busy = 0;
       may_garbage_collect = false;
 
-      save_m_keys = vim_strsave(mp->m_keys);
+      save_m_keys = xstrdup((char *)mp->m_keys);
       if (save_m_luaref == LUA_NOREF) {
-        save_m_str = vim_strsave((char_u *)mp->m_str);
+        save_m_str = xstrdup(mp->m_str);
       }
       map_str = eval_map_expr(mp, NUL);
 
@@ -2207,13 +2207,13 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
       // If an error was displayed and the expression returns an empty
       // string, generate a <Nop> to allow for a redraw.
       if (prev_did_emsg != did_emsg && (map_str == NULL || *map_str == NUL)) {
-        char_u buf[4];
+        char buf[4];
         xfree(map_str);
-        buf[0] = K_SPECIAL;
-        buf[1] = KS_EXTRA;
+        buf[0] = (char)K_SPECIAL;
+        buf[1] = (char)KS_EXTRA;
         buf[2] = KE_IGNORE;
         buf[3] = NUL;
-        map_str = vim_strsave(buf);
+        map_str = xstrdup(buf);
         if (State & MODE_CMDLINE) {
           // redraw the command below the error
           msg_didout = true;
@@ -2227,7 +2227,7 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
       vgetc_busy = save_vgetc_busy;
       may_garbage_collect = save_may_garbage_collect;
     } else {
-      map_str = (char_u *)mp->m_str;
+      map_str = mp->m_str;
     }
 
     // Insert the 'to' part in the typebuf.tb_buf.
@@ -2242,18 +2242,18 @@ static int handle_mapping(int *keylenp, bool *timedout, int *mapdepth)
       // If this is a LANGMAP mapping, then we didn't record the keys
       // at the start of the function and have to record them now.
       if (keylen > typebuf.tb_maplen && (mp->m_mode & MODE_LANGMAP) != 0) {
-        gotchars(map_str, STRLEN(map_str));
+        gotchars((char_u *)map_str, STRLEN(map_str));
       }
 
       if (save_m_noremap != REMAP_YES) {
         noremap = save_m_noremap;
-      } else if (STRNCMP(map_str, save_m_keys != NULL ? save_m_keys : mp->m_keys,
+      } else if (STRNCMP(map_str, save_m_keys != NULL ? save_m_keys : (char *)mp->m_keys,
                          (size_t)keylen) != 0) {
         noremap = REMAP_YES;
       } else {
         noremap = REMAP_SKIP;
       }
-      i = ins_typebuf((char *)map_str, noremap, 0, true, cmd_silent || save_m_silent);
+      i = ins_typebuf(map_str, noremap, 0, true, cmd_silent || save_m_silent);
       if (save_m_expr) {
         xfree(map_str);
       }
diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index 060db3b3b1..84c01e0140 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -599,7 +599,7 @@ EXTERN int inhibit_delete_count INIT(= 0);
 #define DBCS_DEBUG     (-1)
 
 /// Encoding used when 'fencs' is set to "default"
-EXTERN char_u *fenc_default INIT(= NULL);
+EXTERN char *fenc_default INIT(= NULL);
 
 /// "State" is the main state of Vim.
 /// There are other variables that modify the state:
diff --git a/src/nvim/hardcopy.c b/src/nvim/hardcopy.c
index 85f59f39de..903349dcae 100644
--- a/src/nvim/hardcopy.c
+++ b/src/nvim/hardcopy.c
@@ -2292,7 +2292,7 @@ int mch_print_init(prt_settings_T *psettings, char_u *jobname, int forceit)
 
   // If the user didn't specify a file name, use a temp file.
   if (psettings->outfile == NULL) {
-    prt_ps_file_name = vim_tempname();
+    prt_ps_file_name = (char_u *)vim_tempname();
     if (prt_ps_file_name == NULL) {
       emsg(_(e_notmp));
       return FAIL;
diff --git a/src/nvim/help.c b/src/nvim/help.c
index 245d80489f..235f64744a 100644
--- a/src/nvim/help.c
+++ b/src/nvim/help.c
@@ -180,7 +180,7 @@ void ex_help(exarg_T *eap)
   // It is needed for do_tag top open folds under the cursor.
   KeyTyped = old_KeyTyped;
 
-  do_tag((char_u *)tag, DT_HELP, 1, false, true);
+  do_tag(tag, DT_HELP, 1, false, true);
 
   // Delete the empty buffer if we're not using it.  Careful: autocommands
   // may have jumped to another window, check that the buffer is not in a
@@ -658,13 +658,13 @@ void fix_help_buffer(void)
 
   if (!syntax_present(curwin)) {
     for (lnum = 1; lnum <= curbuf->b_ml.ml_line_count; lnum++) {
-      line = (char *)ml_get_buf(curbuf, lnum, false);
+      line = ml_get_buf(curbuf, lnum, false);
       const size_t len = STRLEN(line);
       if (in_example && len > 0 && !ascii_iswhite(line[0])) {
         // End of example: non-white or '<' in first column.
         if (line[0] == '<') {
           // blank-out a '<' in the first column
-          line = (char *)ml_get_buf(curbuf, lnum, true);
+          line = ml_get_buf(curbuf, lnum, true);
           line[0] = ' ';
         }
         in_example = false;
@@ -672,12 +672,12 @@ void fix_help_buffer(void)
       if (!in_example && len > 0) {
         if (line[len - 1] == '>' && (len == 1 || line[len - 2] == ' ')) {
           // blank-out a '>' in the last column (start of example)
-          line = (char *)ml_get_buf(curbuf, lnum, true);
+          line = ml_get_buf(curbuf, lnum, true);
           line[len - 1] = ' ';
           in_example = true;
         } else if (line[len - 1] == '~') {
           // blank-out a '~' at the end of line (header marker)
-          line = (char *)ml_get_buf(curbuf, lnum, true);
+          line = ml_get_buf(curbuf, lnum, true);
           line[len - 1] = ' ';
         }
       }
@@ -694,7 +694,7 @@ void fix_help_buffer(void)
           && TOLOWER_ASC(fname[7]) == 'x'
           && fname[8] == NUL)) {
     for (lnum = 1; lnum < curbuf->b_ml.ml_line_count; lnum++) {
-      line = (char *)ml_get_buf(curbuf, lnum, false);
+      line = ml_get_buf(curbuf, lnum, false);
       if (strstr(line, "*local-additions*") == NULL) {
         continue;
       }
@@ -1167,8 +1167,7 @@ void ex_helptags(exarg_T *eap)
   } else {
     ExpandInit(&xpc);
     xpc.xp_context = EXPAND_DIRECTORIES;
-    dirname = (char *)ExpandOne(&xpc, (char_u *)eap->arg, NULL,
-                                WILD_LIST_NOTFOUND|WILD_SILENT, WILD_EXPAND_FREE);
+    dirname = ExpandOne(&xpc, eap->arg, NULL, WILD_LIST_NOTFOUND|WILD_SILENT, WILD_EXPAND_FREE);
     if (dirname == NULL || !os_isdir(dirname)) {
       semsg(_("E150: Not a directory: %s"), eap->arg);
     } else {
diff --git a/src/nvim/highlight_group.c b/src/nvim/highlight_group.c
index 412fe3509d..7e5fd52243 100644
--- a/src/nvim/highlight_group.c
+++ b/src/nvim/highlight_group.c
@@ -553,12 +553,12 @@ void init_highlight(bool both, bool reset)
 
   // Try finding the color scheme file.  Used when a color file was loaded
   // and 'background' or 't_Co' is changed.
-  char_u *p = get_var_value("g:colors_name");
+  char *p = (char *)get_var_value("g:colors_name");
   if (p != NULL) {
     // Value of g:colors_name could be freed in load_colors() and make
     // p invalid, so copy it.
-    char_u *copy_p = vim_strsave(p);
-    bool okay = load_colors(copy_p);
+    char *copy_p = xstrdup(p);
+    bool okay = load_colors((char_u *)copy_p);
     xfree(copy_p);
     if (okay) {
       return;
diff --git a/src/nvim/if_cscope.c b/src/nvim/if_cscope.c
index 85534ebcff..719899d0b8 100644
--- a/src/nvim/if_cscope.c
+++ b/src/nvim/if_cscope.c
@@ -228,16 +228,16 @@ void ex_cstag(exarg_T *eap)
         }
 
         if (cs_check_for_tags()) {
-          ret = do_tag((char_u *)eap->arg, DT_JUMP, 0, eap->forceit, false);
+          ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, false);
         }
       }
     } else if (cs_check_for_tags()) {
-      ret = do_tag((char_u *)eap->arg, DT_JUMP, 0, eap->forceit, false);
+      ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, false);
     }
     break;
   case 1:
     if (cs_check_for_tags()) {
-      ret = do_tag((char_u *)eap->arg, DT_JUMP, 0, eap->forceit, false);
+      ret = do_tag(eap->arg, DT_JUMP, 0, eap->forceit, false);
       if (ret == false) {
         if (msg_col) {
           msg_putchar('\n');
@@ -1003,7 +1003,7 @@ static bool cs_find_common(char *opt, char *pat, int forceit, int verbose, bool
   if (qfpos != NULL && *qfpos != '0') {
     // Fill error list.
     FILE *f;
-    char_u *tmp = vim_tempname();
+    char_u *tmp = (char_u *)vim_tempname();
     qf_info_T *qi = NULL;
     win_T *wp = NULL;
 
@@ -1053,7 +1053,7 @@ static bool cs_find_common(char *opt, char *pat, int forceit, int verbose, bool
 
     (void)cs_manage_matches(matches, contexts, matched, Store);
 
-    return do_tag((char_u *)pat, DT_CSCOPE, 0, forceit, verbose);
+    return do_tag(pat, DT_CSCOPE, 0, forceit, verbose);
   }
 }
 
diff --git a/src/nvim/indent.c b/src/nvim/indent.c
index a41a396abc..af5bcd7d2a 100644
--- a/src/nvim/indent.c
+++ b/src/nvim/indent.c
@@ -362,7 +362,7 @@ int get_indent_lnum(linenr_T lnum)
 // "buf".
 int get_indent_buf(buf_T *buf, linenr_T lnum)
 {
-  return get_indent_str_vtab((char *)ml_get_buf(buf, lnum, false),
+  return get_indent_str_vtab(ml_get_buf(buf, lnum, false),
                              curbuf->b_p_ts,
                              buf->b_p_vts_array,
                              false);
@@ -874,7 +874,7 @@ bool may_do_si(void)
   return curbuf->b_p_si && !curbuf->b_p_cin && *curbuf->b_p_inde == NUL && !p_paste;
 }
 
-// Get indent level from 'indentexpr'.
+/// Get indent level from 'indentexpr'.
 int get_expr_indent(void)
 {
   int indent = -1;
@@ -898,8 +898,8 @@ int get_expr_indent(void)
 
   // Need to make a copy, the 'indentexpr' option could be changed while
   // evaluating it.
-  char_u *inde_copy = vim_strsave((char_u *)curbuf->b_p_inde);
-  indent = (int)eval_to_number((char *)inde_copy);
+  char *inde_copy = xstrdup(curbuf->b_p_inde);
+  indent = (int)eval_to_number(inde_copy);
   xfree(inde_copy);
 
   if (use_sandbox) {
diff --git a/src/nvim/indent_c.c b/src/nvim/indent_c.c
index 5941473825..c7f37790b6 100644
--- a/src/nvim/indent_c.c
+++ b/src/nvim/indent_c.c
@@ -1838,7 +1838,7 @@ int get_c_indent(void)
   int cur_amount = MAXCOL;
   colnr_T col;
   char_u *theline;
-  char_u *linecopy;
+  char *linecopy;
   pos_T *trypos;
   pos_T *comment_pos;
   pos_T *tryposBrace = NULL;
@@ -1893,7 +1893,7 @@ int get_c_indent(void)
   // Get a copy of the current contents of the line.
   // This is required, because only the most recent line obtained with
   // ml_get is valid!
-  linecopy = vim_strsave((char_u *)ml_get(cur_curpos.lnum));
+  linecopy = xstrdup(ml_get(cur_curpos.lnum));
 
   // In insert mode and the cursor is on a ')' truncate the line at the
   // cursor position.  We don't want to line up with the matching '(' when
@@ -1906,7 +1906,7 @@ int get_c_indent(void)
     linecopy[curwin->w_cursor.col] = NUL;
   }
 
-  theline = (char_u *)skipwhite((char *)linecopy);
+  theline = (char_u *)skipwhite(linecopy);
 
   // move the cursor to the start of the line
 
diff --git a/src/nvim/insexpand.c b/src/nvim/insexpand.c
index dce72a2611..686461ce60 100644
--- a/src/nvim/insexpand.c
+++ b/src/nvim/insexpand.c
@@ -132,10 +132,10 @@ typedef struct compl_S compl_T;
 struct compl_S {
   compl_T *cp_next;
   compl_T *cp_prev;
-  char_u *cp_str;                ///< matched text
-  char_u *(cp_text[CPT_COUNT]);  ///< text for the menu
+  char *cp_str;                  ///< matched text
+  char *(cp_text[CPT_COUNT]);    ///< text for the menu
   typval_T cp_user_data;
-  char_u *cp_fname;              ///< file containing the match, allocated when
+  char *cp_fname;                ///< file containing the match, allocated when
                                  ///< cp_flags has CP_FREE_FNAME
   int cp_flags;                  ///< CP_ values
   int cp_number;                 ///< sequence number
@@ -191,7 +191,7 @@ static bool compl_enter_selects = false;
 
 /// When "compl_leader" is not NULL only matches that start with this string
 /// are used.
-static char_u *compl_leader = NULL;
+static char *compl_leader = NULL;
 
 static bool compl_get_longest = false;  ///< put longest common string in compl_leader
 
@@ -802,7 +802,7 @@ static int ins_compl_add(char *const str, int len, char *const fname, char *cons
   if (flags & CP_ORIGINAL_TEXT) {
     match->cp_number = 0;
   }
-  match->cp_str = (char_u *)xstrnsave(str, (size_t)len);
+  match->cp_str = xstrnsave(str, (size_t)len);
 
   // match-fname is:
   // - compl_curr_match->cp_fname if it is a string equal to fname.
@@ -814,7 +814,7 @@ static int ins_compl_add(char *const str, int len, char *const fname, char *cons
       && STRCMP(fname, compl_curr_match->cp_fname) == 0) {
     match->cp_fname = compl_curr_match->cp_fname;
   } else if (fname != NULL) {
-    match->cp_fname = vim_strsave((char_u *)fname);
+    match->cp_fname = xstrdup(fname);
     flags |= CP_FREE_FNAME;
   } else {
     match->cp_fname = NULL;
@@ -829,9 +829,7 @@ static int ins_compl_add(char *const str, int len, char *const fname, char *cons
         continue;
       }
       if (*cptext[i] != NUL) {
-        match->cp_text[i] = (cptext_allocated
-                             ? (char_u *)cptext[i]
-                             : (char_u *)xstrdup(cptext[i]));
+        match->cp_text[i] = (cptext_allocated ? cptext[i] : xstrdup(cptext[i]));
       } else if (cptext_allocated) {
         xfree(cptext[i]);
       }
@@ -898,11 +896,11 @@ static void ins_compl_longest_match(compl_T *match)
 
   if (compl_leader == NULL) {
     // First match, use it as a whole.
-    compl_leader = vim_strsave(match->cp_str);
+    compl_leader = xstrdup(match->cp_str);
 
     had_match = (curwin->w_cursor.col > compl_col);
     ins_compl_delete();
-    ins_bytes((char *)compl_leader + get_compl_len());
+    ins_bytes(compl_leader + get_compl_len());
     ins_redraw(false);
 
     // When the match isn't there (to avoid matching itself) remove it
@@ -916,8 +914,8 @@ static void ins_compl_longest_match(compl_T *match)
   }
 
   // Reduce the text if this match differs from compl_leader.
-  p = compl_leader;
-  s = match->cp_str;
+  p = (char_u *)compl_leader;
+  s = (char_u *)match->cp_str;
   while (*p != NUL) {
     c1 = utf_ptr2char((char *)p);
     c2 = utf_ptr2char((char *)s);
@@ -936,7 +934,7 @@ static void ins_compl_longest_match(compl_T *match)
     *p = NUL;
     had_match = (curwin->w_cursor.col > compl_col);
     ins_compl_delete();
-    ins_bytes((char *)compl_leader + get_compl_len());
+    ins_bytes(compl_leader + get_compl_len());
     ins_redraw(false);
 
     // When the match isn't there (to avoid matching itself) remove it
@@ -1131,7 +1129,7 @@ static int ins_compl_build_pum(void)
   do {
     if (!match_at_original_text(compl)
         && (compl_leader == NULL
-            || ins_compl_equal(compl, compl_leader, (size_t)lead_len))) {
+            || ins_compl_equal(compl, (char_u *)compl_leader, (size_t)lead_len))) {
       compl_match_arraysize++;
     }
     compl = compl->cp_next;
@@ -1156,7 +1154,7 @@ static int ins_compl_build_pum(void)
   do {
     if (!match_at_original_text(compl)
         && (compl_leader == NULL
-            || ins_compl_equal(compl, compl_leader, (size_t)lead_len))) {
+            || ins_compl_equal(compl, (char_u *)compl_leader, (size_t)lead_len))) {
       if (!shown_match_ok) {
         if (compl == compl_shown_match || did_find_shown_match) {
           // This item is the shown match or this is the
@@ -1173,16 +1171,16 @@ static int ins_compl_build_pum(void)
       }
 
       if (compl->cp_text[CPT_ABBR] != NULL) {
-        compl_match_array[i].pum_text = compl->cp_text[CPT_ABBR];
+        compl_match_array[i].pum_text = (char_u *)compl->cp_text[CPT_ABBR];
       } else {
-        compl_match_array[i].pum_text = compl->cp_str;
+        compl_match_array[i].pum_text = (char_u *)compl->cp_str;
       }
-      compl_match_array[i].pum_kind = compl->cp_text[CPT_KIND];
-      compl_match_array[i].pum_info = compl->cp_text[CPT_INFO];
+      compl_match_array[i].pum_kind = (char_u *)compl->cp_text[CPT_KIND];
+      compl_match_array[i].pum_info = (char_u *)compl->cp_text[CPT_INFO];
       if (compl->cp_text[CPT_MENU] != NULL) {
-        compl_match_array[i++].pum_extra = compl->cp_text[CPT_MENU];
+        compl_match_array[i++].pum_extra = (char_u *)compl->cp_text[CPT_MENU];
       } else {
-        compl_match_array[i++].pum_extra = compl->cp_fname;
+        compl_match_array[i++].pum_extra = (char_u *)compl->cp_fname;
       }
     }
 
@@ -1236,8 +1234,8 @@ void ins_compl_show_pum(void)
   } else {
     // popup menu already exists, only need to find the current item.
     for (int i = 0; i < compl_match_arraysize; i++) {
-      if (compl_match_array[i].pum_text == compl_shown_match->cp_str
-          || compl_match_array[i].pum_text == compl_shown_match->cp_text[CPT_ABBR]) {
+      if (compl_match_array[i].pum_text == (char_u *)compl_shown_match->cp_str
+          || compl_match_array[i].pum_text == (char_u *)compl_shown_match->cp_text[CPT_ABBR]) {
         cur = i;
         break;
       }
@@ -1649,7 +1647,7 @@ int ins_compl_bs(void)
   line = get_cursor_line_ptr();
 
   xfree(compl_leader);
-  compl_leader = (char_u *)xstrnsave(line + compl_col, (size_t)(p_off - (ptrdiff_t)compl_col));
+  compl_leader = xstrnsave(line + compl_col, (size_t)(p_off - (ptrdiff_t)compl_col));
 
   ins_compl_new_leader();
   if (compl_shown_match != NULL) {
@@ -1678,7 +1676,7 @@ static void ins_compl_new_leader(void)
 {
   ins_compl_del_pum();
   ins_compl_delete();
-  ins_bytes((char *)compl_leader + get_compl_len());
+  ins_bytes(compl_leader + get_compl_len());
   compl_used_match = false;
 
   if (compl_started) {
@@ -1743,8 +1741,8 @@ void ins_compl_addleader(int c)
   }
 
   xfree(compl_leader);
-  compl_leader = (char_u *)xstrnsave(get_cursor_line_ptr() + compl_col,
-                                     (size_t)(curwin->w_cursor.col - compl_col));
+  compl_leader = xstrnsave(get_cursor_line_ptr() + compl_col,
+                           (size_t)(curwin->w_cursor.col - compl_col));
   ins_compl_new_leader();
 }
 
@@ -1764,7 +1762,7 @@ static void ins_compl_restart(void)
 }
 
 /// Set the first match, the original text.
-static void ins_compl_set_original_text(char_u *str)
+static void ins_compl_set_original_text(char *str)
   FUNC_ATTR_NONNULL_ALL
 {
   // Replace the original text entry.
@@ -1772,11 +1770,11 @@ static void ins_compl_set_original_text(char_u *str)
   // be at the last item for backward completion
   if (match_at_original_text(compl_first_match)) {  // safety check
     xfree(compl_first_match->cp_str);
-    compl_first_match->cp_str = vim_strsave(str);
+    compl_first_match->cp_str = xstrdup(str);
   } else if (compl_first_match->cp_prev != NULL
              && match_at_original_text(compl_first_match->cp_prev)) {
     xfree(compl_first_match->cp_prev->cp_str);
-    compl_first_match->cp_prev->cp_str = vim_strsave(str);
+    compl_first_match->cp_prev->cp_str = xstrdup(str);
   }
 }
 
@@ -1789,7 +1787,7 @@ void ins_compl_addfrommatch(void)
   int c;
   compl_T *cp;
   assert(compl_shown_match != NULL);
-  p = compl_shown_match->cp_str;
+  p = (char_u *)compl_shown_match->cp_str;
   if ((int)STRLEN(p) <= len) {   // the match is too short
     // When still at the original match use the first entry that matches
     // the leader.
@@ -1801,8 +1799,8 @@ void ins_compl_addfrommatch(void)
     for (cp = compl_shown_match->cp_next; cp != NULL
          && !is_first_match(cp); cp = cp->cp_next) {
       if (compl_leader == NULL
-          || ins_compl_equal(cp, compl_leader, STRLEN(compl_leader))) {
-        p = cp->cp_str;
+          || ins_compl_equal(cp, (char_u *)compl_leader, STRLEN(compl_leader))) {
+        p = (char_u *)cp->cp_str;
         break;
       }
     }
@@ -1955,7 +1953,7 @@ static bool ins_compl_stop(const int c, const int prev_mode, bool retval)
     // CTRL-E then don't use the current match.
     char_u *ptr;
     if (compl_curr_match != NULL && compl_used_match && c != Ctrl_E) {
-      ptr = compl_curr_match->cp_str;
+      ptr = (char_u *)compl_curr_match->cp_str;
     } else {
       ptr = NULL;
     }
@@ -2006,7 +2004,7 @@ static bool ins_compl_stop(const int c, const int prev_mode, bool retval)
     ins_compl_delete();
     char_u *p = NULL;
     if (compl_leader != NULL) {
-      p = compl_leader;
+      p = (char_u *)compl_leader;
     } else if (compl_first_match != NULL) {
       p = (char_u *)compl_orig_text;
     }
@@ -2168,7 +2166,7 @@ static void ins_compl_fixRedoBufForLeader(char_u *ptr_arg)
 
   if (ptr == NULL) {
     if (compl_leader != NULL) {
-      ptr = compl_leader;
+      ptr = (char_u *)compl_leader;
     } else {
       return;        // nothing to do
     }
@@ -2919,14 +2917,14 @@ static char_u *ins_comp_get_next_word_or_line(buf_T *ins_buf, pos_T *cur_match_p
                                               bool *cont_s_ipos)
 {
   *match_len = 0;
-  char_u *ptr = ml_get_buf(ins_buf, cur_match_pos->lnum, false) + cur_match_pos->col;
+  char_u *ptr = (char_u *)ml_get_buf(ins_buf, cur_match_pos->lnum, false) + cur_match_pos->col;
   int len;
   if (ctrl_x_mode_line_or_eval()) {
     if (compl_status_adding()) {
       if (cur_match_pos->lnum >= ins_buf->b_ml.ml_line_count) {
         return NULL;
       }
-      ptr = ml_get_buf(ins_buf, cur_match_pos->lnum + 1, false);
+      ptr = (char_u *)ml_get_buf(ins_buf, cur_match_pos->lnum + 1, false);
       if (!p_paste) {
         ptr = (char_u *)skipwhite((char *)ptr);
       }
@@ -2954,7 +2952,7 @@ static char_u *ins_comp_get_next_word_or_line(buf_T *ins_buf, pos_T *cur_match_p
         // normal command "J" was used. IOSIZE is always greater than
         // compl_length, so the next STRNCPY always works -- Acevedo
         STRNCPY(IObuff, ptr, len);  // NOLINT(runtime/printf)
-        ptr = ml_get_buf(ins_buf, cur_match_pos->lnum + 1, false);
+        ptr = (char_u *)ml_get_buf(ins_buf, cur_match_pos->lnum + 1, false);
         tmp_ptr = ptr = (char_u *)skipwhite((char *)ptr);
         // Find start of next word.
         tmp_ptr = find_word_start(tmp_ptr);
@@ -3275,7 +3273,7 @@ static int ins_compl_get_exp(pos_T *ini)
 static void ins_compl_update_shown_match(void)
 {
   while (!ins_compl_equal(compl_shown_match,
-                          compl_leader, STRLEN(compl_leader))
+                          (char_u *)compl_leader, STRLEN(compl_leader))
          && compl_shown_match->cp_next != NULL
          && !is_first_match(compl_shown_match->cp_next)) {
     compl_shown_match = compl_shown_match->cp_next;
@@ -3284,10 +3282,10 @@ static void ins_compl_update_shown_match(void)
   // If we didn't find it searching forward, and compl_shows_dir is
   // backward, find the last match.
   if (compl_shows_dir_backward()
-      && !ins_compl_equal(compl_shown_match, compl_leader, STRLEN(compl_leader))
+      && !ins_compl_equal(compl_shown_match, (char_u *)compl_leader, STRLEN(compl_leader))
       && (compl_shown_match->cp_next == NULL
           || is_first_match(compl_shown_match->cp_next))) {
-    while (!ins_compl_equal(compl_shown_match, compl_leader, STRLEN(compl_leader))
+    while (!ins_compl_equal(compl_shown_match, (char_u *)compl_leader, STRLEN(compl_leader))
            && compl_shown_match->cp_prev != NULL
            && !is_first_match(compl_shown_match->cp_prev)) {
       compl_shown_match = compl_shown_match->cp_prev;
@@ -3321,7 +3319,7 @@ void ins_compl_delete(void)
 /// "in_compl_func" is true when called from complete_check().
 void ins_compl_insert(bool in_compl_func)
 {
-  ins_bytes((char *)compl_shown_match->cp_str + get_compl_len());
+  ins_bytes(compl_shown_match->cp_str + get_compl_len());
   compl_used_match = !match_at_original_text(compl_shown_match);
 
   dict_T *dict = ins_compl_dict_alloc(compl_shown_match);
@@ -3346,7 +3344,7 @@ static void ins_compl_show_filename(void)
   // the text that fits in "space" between "s" and "e".
   char *s;
   char *e;
-  for (s = e = (char *)compl_shown_match->cp_fname; *e != NUL; MB_PTR_ADV(e)) {
+  for (s = e = compl_shown_match->cp_fname; *e != NUL; MB_PTR_ADV(e)) {
     space -= ptr2cells(e);
     while (space < 0) {
       space += ptr2cells(s);
@@ -3355,7 +3353,7 @@ static void ins_compl_show_filename(void)
   }
   msg_hist_off = true;
   vim_snprintf((char *)IObuff, IOSIZE, "%s %s%s", lead,
-               (char_u *)s > compl_shown_match->cp_fname ? "<" : "", s);
+               s > compl_shown_match->cp_fname ? "<" : "", s);
   msg((char *)IObuff);
   msg_hist_off = false;
   redraw_cmdline = false;  // don't overwrite!
@@ -3432,7 +3430,7 @@ static int find_next_completion_match(bool allow_get_expansion, int todo, bool a
     if (!match_at_original_text(compl_shown_match)
         && compl_leader != NULL
         && !ins_compl_equal(compl_shown_match,
-                            compl_leader, STRLEN(compl_leader))) {
+                            (char_u *)compl_leader, STRLEN(compl_leader))) {
       todo++;
     } else {
       // Remember a matching item.
@@ -3519,7 +3517,7 @@ static int ins_compl_next(bool allow_get_expansion, int count, bool insert_match
     if (!compl_get_longest || compl_used_match) {
       ins_compl_insert(in_compl_func);
     } else {
-      ins_bytes((char *)compl_leader + get_compl_len());
+      ins_bytes(compl_leader + get_compl_len());
     }
   } else {
     compl_used_match = false;
diff --git a/src/nvim/lua/converter.c b/src/nvim/lua/converter.c
index 49d49f76b9..21dd5139d7 100644
--- a/src/nvim/lua/converter.c
+++ b/src/nvim/lua/converter.c
@@ -388,12 +388,12 @@ nlua_pop_typval_table_processing_end:
       LuaCFunctionState *state = xmalloc(sizeof(LuaCFunctionState));
       state->lua_callable.func_ref = nlua_ref_global(lstate, -1);
 
-      char_u *name = register_cfunc(&nlua_CFunction_func_call,
-                                    &nlua_CFunction_func_free,
-                                    state);
+      char *name = (char *)register_cfunc(&nlua_CFunction_func_call,
+                                          &nlua_CFunction_func_free,
+                                          state);
 
       cur.tv->v_type = VAR_FUNC;
-      cur.tv->vval.v_string = (char *)vim_strsave(name);
+      cur.tv->vval.v_string = xstrdup(name);
       break;
     }
     case LUA_TUSERDATA: {
diff --git a/src/nvim/lua/stdlib.c b/src/nvim/lua/stdlib.c
index 1b874e673a..e3d6a7eec8 100644
--- a/src/nvim/lua/stdlib.c
+++ b/src/nvim/lua/stdlib.c
@@ -111,7 +111,7 @@ static int regex_match_line(lua_State *lstate)
     return luaL_error(lstate, "invalid row");
   }
 
-  char_u *line = ml_get_buf(buf, rownr + 1, false);
+  char_u *line = (char_u *)ml_get_buf(buf, rownr + 1, false);
   size_t len = STRLEN(line);
 
   if (start < 0 || (size_t)start > len) {
diff --git a/src/nvim/lua/treesitter.c b/src/nvim/lua/treesitter.c
index 65e024b707..971a47f8c9 100644
--- a/src/nvim/lua/treesitter.c
+++ b/src/nvim/lua/treesitter.c
@@ -332,7 +332,7 @@ static const char *input_cb(void *payload, uint32_t byte_index, TSPoint position
     *bytes_read = 0;
     return "";
   }
-  char *line = (char *)ml_get_buf(bp, (linenr_T)position.row + 1, false);
+  char *line = ml_get_buf(bp, (linenr_T)position.row + 1, false);
   size_t len = STRLEN(line);
   if (position.column > len) {
     *bytes_read = 0;
diff --git a/src/nvim/macros.h b/src/nvim/macros.h
index b84539852f..1024ca5015 100644
--- a/src/nvim/macros.h
+++ b/src/nvim/macros.h
@@ -54,7 +54,7 @@
 #define ASCII_ISALNUM(c) (ASCII_ISALPHA(c) || ascii_isdigit(c))
 
 // Returns empty string if it is NULL.
-#define EMPTY_IF_NULL(x) (char *)((x) ? (x) : (char_u *)"")
+#define EMPTY_IF_NULL(x) ((x) ? (x) : "")
 
 /// Adjust chars in a language according to 'langmap' option.
 /// NOTE that there is no noticeable overhead if 'langmap' is not set.
diff --git a/src/nvim/mapping.c b/src/nvim/mapping.c
index 923eea145c..94b432a553 100644
--- a/src/nvim/mapping.c
+++ b/src/nvim/mapping.c
@@ -303,7 +303,7 @@ static void set_maparg_rhs(const char *const orig_rhs, const size_t orig_rhs_len
       // NB: replace_termcodes may produce an empty string even if orig_rhs is non-empty
       // (e.g. a single ^V, see :h map-empty-rhs)
       mapargs->rhs_is_noop = orig_rhs_len != 0 && mapargs->rhs_len == 0;
-      mapargs->rhs = (char_u *)replaced;
+      mapargs->rhs = replaced;
     }
   } else {
     char tmp_buf[64];
@@ -313,7 +313,7 @@ static void set_maparg_rhs(const char *const orig_rhs, const size_t orig_rhs_len
     // stores <lua>ref_no<cr> in map_str
     mapargs->rhs_len = (size_t)vim_snprintf(S_LEN(tmp_buf), "%c%c%c%d\r", K_SPECIAL,
                                             (char_u)KS_EXTRA, KE_LUA, rhs_lua);
-    mapargs->rhs = vim_strsave((char_u *)tmp_buf);
+    mapargs->rhs = xstrdup(tmp_buf);
   }
 }
 
@@ -439,7 +439,7 @@ static int str_to_mapargs(const char_u *strargs, bool is_unmap, MapArguments *ma
 ///              and "desc" fields are used.
 ///              "rhs", "rhs_lua", "orig_rhs" fields are cleared if "simplified" is false.
 /// @param sid  -1 to use current_sctx
-static void map_add(buf_T *buf, mapblock_T **map_table, mapblock_T **abbr_table, const char_u *keys,
+static void map_add(buf_T *buf, mapblock_T **map_table, mapblock_T **abbr_table, const char *keys,
                     MapArguments *args, int noremap, int mode, bool is_abbr, scid_T sid,
                     linenr_T lnum, bool simplified)
 {
@@ -454,8 +454,8 @@ static void map_add(buf_T *buf, mapblock_T **map_table, mapblock_T **abbr_table,
     }
   }
 
-  mp->m_keys = vim_strsave(keys);
-  mp->m_str = (char *)args->rhs;
+  mp->m_keys = (uint8_t *)xstrdup(keys);
+  mp->m_str = args->rhs;
   mp->m_orig_str = (char *)args->orig_rhs;
   mp->m_luaref = args->rhs_lua;
   if (!simplified) {
@@ -767,7 +767,7 @@ static int buf_do_map(int maptype, MapArguments *args, int mode, bool is_abbrev,
                     XFREE_CLEAR(mp->m_str);
                     XFREE_CLEAR(mp->m_orig_str);
                   }
-                  mp->m_str = (char *)args->rhs;
+                  mp->m_str = args->rhs;
                   mp->m_orig_str = (char *)args->orig_rhs;
                   mp->m_luaref = args->rhs_lua;
                   if (!keyround1_simplified) {
@@ -846,7 +846,7 @@ static int buf_do_map(int maptype, MapArguments *args, int mode, bool is_abbrev,
     }
 
     // Get here when adding a new entry to the maphash[] list or abbrlist.
-    map_add(buf, map_table, abbr_table, lhs, args, noremap, mode, is_abbrev,
+    map_add(buf, map_table, abbr_table, (char *)lhs, args, noremap, mode, is_abbrev,
             -1,  // sid
             0,   // lnum
             keyround1_simplified);
@@ -1265,7 +1265,7 @@ int ExpandMappings(regmatch_T *regmatch, int *num_file, char ***file)
   int hash;
   int count;
   int round;
-  char_u *p;
+  char *p;
   int i;
 
   *num_file = 0;                    // return values in case of FAIL
@@ -1278,28 +1278,28 @@ int ExpandMappings(regmatch_T *regmatch, int *num_file, char ***file)
 
     for (i = 0; i < 7; i++) {
       if (i == 0) {
-        p = (char_u *)"<silent>";
+        p = "<silent>";
       } else if (i == 1) {
-        p = (char_u *)"<unique>";
+        p = "<unique>";
       } else if (i == 2) {
-        p = (char_u *)"<script>";
+        p = "<script>";
       } else if (i == 3) {
-        p = (char_u *)"<expr>";
+        p = "<expr>";
       } else if (i == 4 && !expand_buffer) {
-        p = (char_u *)"<buffer>";
+        p = "<buffer>";
       } else if (i == 5) {
-        p = (char_u *)"<nowait>";
+        p = "<nowait>";
       } else if (i == 6) {
-        p = (char_u *)"<special>";
+        p = "<special>";
       } else {
         continue;
       }
 
-      if (vim_regexec(regmatch, (char *)p, (colnr_T)0)) {
+      if (vim_regexec(regmatch, p, (colnr_T)0)) {
         if (round == 1) {
           count++;
         } else {
-          (*file)[count++] = (char *)vim_strsave(p);
+          (*file)[count++] = xstrdup(p);
         }
       }
     }
@@ -1317,12 +1317,12 @@ int ExpandMappings(regmatch_T *regmatch, int *num_file, char ***file)
       }
       for (; mp; mp = mp->m_next) {
         if (mp->m_mode & expand_mapmodes) {
-          p = translate_mapping(mp->m_keys, CPO_TO_CPO_FLAGS);
-          if (p != NULL && vim_regexec(regmatch, (char *)p, (colnr_T)0)) {
+          p = (char *)translate_mapping(mp->m_keys, CPO_TO_CPO_FLAGS);
+          if (p != NULL && vim_regexec(regmatch, p, (colnr_T)0)) {
             if (round == 1) {
               count++;
             } else {
-              (*file)[count++] = (char *)p;
+              (*file)[count++] = p;
               p = NULL;
             }
           }
@@ -1447,20 +1447,20 @@ bool check_abbr(int c, char_u *ptr, int col, int mincol)
          mp->m_next == NULL ? (mp = mp2, mp2 = NULL) :
          (mp = mp->m_next)) {
       int qlen = mp->m_keylen;
-      char_u *q = mp->m_keys;
+      char *q = (char *)mp->m_keys;
       int match;
 
       if (strchr((const char *)mp->m_keys, K_SPECIAL) != NULL) {
         // Might have K_SPECIAL escaped mp->m_keys.
-        q = vim_strsave(mp->m_keys);
-        vim_unescape_ks(q);
+        q = xstrdup((char *)mp->m_keys);
+        vim_unescape_ks((char_u *)q);
         qlen = (int)STRLEN(q);
       }
       // find entries with right mode and keys
       match = (mp->m_mode & State)
               && qlen == len
               && !STRNCMP(q, ptr, (size_t)len);
-      if (q != mp->m_keys) {
+      if (q != (char *)mp->m_keys) {
         xfree(q);
       }
       if (match) {
@@ -1510,7 +1510,7 @@ bool check_abbr(int c, char_u *ptr, int col, int mincol)
         (void)ins_typebuf((char *)tb, 1, 0, true, mp->m_silent);
       }
       if (mp->m_expr) {
-        s = eval_map_expr(mp, c);
+        s = (char_u *)eval_map_expr(mp, c);
       } else {
         s = (char_u *)mp->m_str;
       }
@@ -1540,16 +1540,16 @@ bool check_abbr(int c, char_u *ptr, int col, int mincol)
 /// special characters.
 ///
 /// @param c  NUL or typed character for abbreviation
-char_u *eval_map_expr(mapblock_T *mp, int c)
+char *eval_map_expr(mapblock_T *mp, int c)
 {
-  char_u *p = NULL;
-  char_u *expr = NULL;
+  char *p = NULL;
+  char *expr = NULL;
 
   // Remove escaping of K_SPECIAL, because "str" is in a format to be used as
   // typeahead.
   if (mp->m_luaref == LUA_NOREF) {
-    expr = vim_strsave((char_u *)mp->m_str);
-    vim_unescape_ks(expr);
+    expr = xstrdup(mp->m_str);
+    vim_unescape_ks((char_u *)expr);
   }
 
   // Forbid changing text or using ":normal" to avoid most of the bad side
@@ -1565,7 +1565,7 @@ char_u *eval_map_expr(mapblock_T *mp, int c)
     Array args = ARRAY_DICT_INIT;
     Object ret = nlua_call_ref(mp->m_luaref, NULL, args, true, &err);
     if (ret.type == kObjectTypeString) {
-      p = (char_u *)xstrndup(ret.data.string.data, ret.data.string.size);
+      p = xstrndup(ret.data.string.data, ret.data.string.size);
     }
     api_free_object(ret);
     if (err.type != kErrorTypeNone) {
@@ -1573,7 +1573,7 @@ char_u *eval_map_expr(mapblock_T *mp, int c)
       api_clear_error(&err);
     }
   } else {
-    p = (char_u *)eval_to_string((char *)expr, NULL, false);
+    p = eval_to_string(expr, NULL, false);
     xfree(expr);
   }
   textlock--;
@@ -1586,13 +1586,13 @@ char_u *eval_map_expr(mapblock_T *mp, int c)
     return NULL;
   }
 
-  char_u *res = NULL;
+  char *res = NULL;
 
   if (mp->m_replace_keycodes) {
-    replace_termcodes((char *)p, STRLEN(p), (char **)&res, REPTERM_DO_LT, NULL, CPO_TO_CPO_FLAGS);
+    replace_termcodes(p, STRLEN(p), &res, REPTERM_DO_LT, NULL, CPO_TO_CPO_FLAGS);
   } else {
     // Escape K_SPECIAL in the result to be able to use the string as typeahead.
-    res = (char_u *)vim_strsave_escape_ks((char *)p);
+    res = vim_strsave_escape_ks(p);
   }
   xfree(p);
 
@@ -2204,10 +2204,10 @@ void f_mapset(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
   xfree(unmap_args.orig_rhs);
 
   if (lhsrawalt != NULL) {
-    map_add(curbuf, map_table, abbr_table, (char_u *)lhsrawalt, &args, noremap, mode, is_abbr,
+    map_add(curbuf, map_table, abbr_table, lhsrawalt, &args, noremap, mode, is_abbr,
             sid, lnum, true);
   }
-  map_add(curbuf, map_table, abbr_table, (char_u *)lhsraw, &args, noremap, mode, is_abbr,
+  map_add(curbuf, map_table, abbr_table, lhsraw, &args, noremap, mode, is_abbr,
           sid, lnum, false);
 }
 
diff --git a/src/nvim/mapping.h b/src/nvim/mapping.h
index 7c48c3bce2..182d1a48cb 100644
--- a/src/nvim/mapping.h
+++ b/src/nvim/mapping.h
@@ -35,7 +35,7 @@ struct map_arguments {
   char_u alt_lhs[MAXMAPLEN + 1];
   size_t alt_lhs_len;
 
-  char_u *rhs;  /// The {rhs} of the mapping.
+  char *rhs;  /// The {rhs} of the mapping.
   size_t rhs_len;
   LuaRef rhs_lua;  /// lua function as {rhs}
   bool rhs_is_noop;  /// True when the {rhs} should be <Nop>.
diff --git a/src/nvim/mark.c b/src/nvim/mark.c
index 7838986edd..a6d0a68323 100644
--- a/src/nvim/mark.c
+++ b/src/nvim/mark.c
@@ -992,22 +992,22 @@ void ex_delmarks(exarg_T *eap)
 void ex_jumps(exarg_T *eap)
 {
   int i;
-  char_u *name;
+  char *name;
 
   cleanup_jumplist(curwin, true);
   // Highlight title
   msg_puts_title(_("\n jump line  col file/text"));
   for (i = 0; i < curwin->w_jumplistlen && !got_int; i++) {
     if (curwin->w_jumplist[i].fmark.mark.lnum != 0) {
-      name = fm_getname(&curwin->w_jumplist[i].fmark, 16);
+      name = (char *)fm_getname(&curwin->w_jumplist[i].fmark, 16);
 
       // Make sure to output the current indicator, even when on an wiped
       // out buffer.  ":filter" may still skip it.
       if (name == NULL && i == curwin->w_jumplistidx) {
-        name = vim_strsave((char_u *)"-invalid-");
+        name = xstrdup("-invalid-");
       }
       // apply :filter /pat/ or file name not available
-      if (name == NULL || message_filtered((char *)name)) {
+      if (name == NULL || message_filtered(name)) {
         xfree(name);
         continue;
       }
@@ -1022,7 +1022,7 @@ void ex_jumps(exarg_T *eap)
                i > curwin->w_jumplistidx ? i - curwin->w_jumplistidx : curwin->w_jumplistidx - i,
                curwin->w_jumplist[i].fmark.mark.lnum, curwin->w_jumplist[i].fmark.mark.col);
       msg_outtrans((char *)IObuff);
-      msg_outtrans_attr((char *)name,
+      msg_outtrans_attr(name,
                         curwin->w_jumplist[i].fmark.fnum == curbuf->b_fnum
                         ? HL_ATTR(HLF_D) : 0);
       xfree(name);
@@ -1710,7 +1710,7 @@ void mark_mb_adjustpos(buf_T *buf, pos_T *lp)
   FUNC_ATTR_NONNULL_ALL
 {
   if (lp->col > 0 || lp->coladd > 1) {
-    const char_u *const p = ml_get_buf(buf, lp->lnum, false);
+    const char_u *const p = (char_u *)ml_get_buf(buf, lp->lnum, false);
     if (*p == NUL || (int)STRLEN(p) < lp->col) {
       lp->col = 0;
     } else {
diff --git a/src/nvim/match.c b/src/nvim/match.c
index b6d700b148..cd8c65cc02 100644
--- a/src/nvim/match.c
+++ b/src/nvim/match.c
@@ -446,7 +446,7 @@ static void next_search_hl(win_T *win, match_T *search_hl, match_T *shl, linenr_
       char_u *ml;
 
       matchcol = shl->rm.startpos[0].col;
-      ml = ml_get_buf(shl->buf, lnum, false) + matchcol;
+      ml = (char_u *)ml_get_buf(shl->buf, lnum, false) + matchcol;
       if (*ml == NUL) {
         matchcol++;
         shl->lnum = 0;
@@ -613,7 +613,7 @@ bool prepare_search_hl_line(win_T *wp, linenr_T lnum, colnr_T mincol, char_u **l
 
     // Need to get the line again, a multi-line regexp may have made it
     // invalid.
-    *line = ml_get_buf(wp->w_buffer, lnum, false);
+    *line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
 
     if (shl->lnum != 0 && shl->lnum <= lnum) {
       if (shl->lnum == lnum) {
@@ -721,7 +721,7 @@ int update_search_hl(win_T *wp, linenr_T lnum, colnr_T col, char_u **line, match
 
         // Need to get the line again, a multi-line regexp
         // may have made it invalid.
-        *line = ml_get_buf(wp->w_buffer, lnum, false);
+        *line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
 
         if (shl->lnum == lnum) {
           shl->startcol = shl->rm.startpos[0].col;
diff --git a/src/nvim/mbyte.c b/src/nvim/mbyte.c
index 116a66e773..83b0609052 100644
--- a/src/nvim/mbyte.c
+++ b/src/nvim/mbyte.c
@@ -1536,7 +1536,7 @@ void show_utf8(void)
 
   // Get the byte length of the char under the cursor, including composing
   // characters.
-  line = get_cursor_pos_ptr();
+  line = (char_u *)get_cursor_pos_ptr();
   len = utfc_ptr2len((char *)line);
   if (len == 0) {
     msg("NUL");
@@ -1891,7 +1891,7 @@ void utf_find_illegal(void)
 
   curwin->w_cursor.coladd = 0;
   for (;;) {
-    p = get_cursor_pos_ptr();
+    p = (char_u *)get_cursor_pos_ptr();
     if (vimconv.vc_type != CONV_NONE) {
       xfree(tofree);
       tofree = (char_u *)string_convert(&vimconv, (char *)p, NULL);
@@ -1908,12 +1908,12 @@ void utf_find_illegal(void)
       if (*p >= 0x80 && (len == 1
                          || utf_char2len(utf_ptr2char((char *)p)) != len)) {
         if (vimconv.vc_type == CONV_NONE) {
-          curwin->w_cursor.col += (colnr_T)(p - get_cursor_pos_ptr());
+          curwin->w_cursor.col += (colnr_T)(p - (char_u *)get_cursor_pos_ptr());
         } else {
           int l;
 
           len = (int)(p - tofree);
-          for (p = get_cursor_pos_ptr(); *p != NUL && len-- > 0; p += l) {
+          for (p = (char_u *)get_cursor_pos_ptr(); *p != NUL && len-- > 0; p += l) {
             l = utf_ptr2len((char *)p);
             curwin->w_cursor.col += l;
           }
@@ -1980,7 +1980,7 @@ void mb_check_adjust_col(void *win_)
 
   // Column 0 is always valid.
   if (oldcol != 0) {
-    char *p = (char *)ml_get_buf(win->w_buffer, win->w_cursor.lnum, false);
+    char *p = ml_get_buf(win->w_buffer, win->w_cursor.lnum, false);
     colnr_T len = (colnr_T)STRLEN(p);
 
     // Empty line or invalid column?
@@ -2114,27 +2114,27 @@ char *enc_skip(char *p)
 char *enc_canonize(char *enc)
   FUNC_ATTR_NONNULL_RET
 {
-  char_u *p, *s;
+  char *p, *s;
   if (STRCMP(enc, "default") == 0) {
     // Use the default encoding as found by set_init_1().
-    return (char *)vim_strsave(fenc_default);
+    return xstrdup(fenc_default);
   }
 
   // copy "enc" to allocated memory, with room for two '-'
-  char_u *r = xmalloc(STRLEN(enc) + 3);
+  char *r = xmalloc(STRLEN(enc) + 3);
   // Make it all lower case and replace '_' with '-'.
   p = r;
-  for (s = (char_u *)enc; *s != NUL; s++) {
+  for (s = enc; *s != NUL; s++) {
     if (*s == '_') {
       *p++ = '-';
     } else {
-      *p++ = (char_u)TOLOWER_ASC(*s);
+      *p++ = (char)TOLOWER_ASC(*s);
     }
   }
   *p = NUL;
 
   // Skip "2byte-" and "8bit-".
-  p = (char_u *)enc_skip((char *)r);
+  p = enc_skip(r);
 
   // Change "microsoft-cp" to "cp".  Used in some spell files.
   if (STRNCMP(p, "microsoft-cp", 12) == 0) {
@@ -2159,17 +2159,17 @@ char *enc_canonize(char *enc)
   }
 
   int i;
-  if (enc_canon_search(p) >= 0) {
+  if (enc_canon_search((char_u *)p) >= 0) {
     // canonical name can be used unmodified
     if (p != r) {
       STRMOVE(r, p);
     }
-  } else if ((i = enc_alias_search(p)) >= 0) {
+  } else if ((i = enc_alias_search((char_u *)p)) >= 0) {
     // alias recognized, get canonical name
     xfree(r);
-    r = vim_strsave((char_u *)enc_canon_table[i].name);
+    r = xstrdup(enc_canon_table[i].name);
   }
-  return (char *)r;
+  return r;
 }
 
 /// Search for an encoding alias of "name".
@@ -2491,7 +2491,7 @@ char_u *string_convert_ext(const vimconv_T *const vcp, char_u *ptr, size_t *lenp
     len = *lenp;
   }
   if (len == 0) {
-    return vim_strsave((char_u *)"");
+    return (char_u *)xstrdup("");
   }
 
   switch (vcp->vc_type) {
diff --git a/src/nvim/memfile.c b/src/nvim/memfile.c
index 9446aaee4f..bb9be0766e 100644
--- a/src/nvim/memfile.c
+++ b/src/nvim/memfile.c
@@ -170,7 +170,7 @@ void mf_close(memfile_T *mfp, bool del_file)
     emsg(_(e_swapclose));
   }
   if (del_file && mfp->mf_fname != NULL) {
-    os_remove((char *)mfp->mf_fname);
+    os_remove(mfp->mf_fname);
   }
 
   // free entries in used list
@@ -210,7 +210,7 @@ void mf_close_file(buf_T *buf, bool getlines)
   mfp->mf_fd = -1;
 
   if (mfp->mf_fname != NULL) {
-    os_remove((char *)mfp->mf_fname);    // delete the swap file
+    os_remove(mfp->mf_fname);    // delete the swap file
     mf_free_fnames(mfp);
   }
 }
@@ -751,8 +751,8 @@ void mf_free_fnames(memfile_T *mfp)
 /// name so we must work out the full path name.
 void mf_set_fnames(memfile_T *mfp, char *fname)
 {
-  mfp->mf_fname = (char_u *)fname;
-  mfp->mf_ffname = (char_u *)FullName_save((char *)mfp->mf_fname, false);
+  mfp->mf_fname = fname;
+  mfp->mf_ffname = (char_u *)FullName_save(mfp->mf_fname, false);
 }
 
 /// Make name of memfile's swapfile a full path.
@@ -762,7 +762,7 @@ void mf_fullname(memfile_T *mfp)
 {
   if (mfp != NULL && mfp->mf_fname != NULL && mfp->mf_ffname != NULL) {
     xfree(mfp->mf_fname);
-    mfp->mf_fname = mfp->mf_ffname;
+    mfp->mf_fname = (char *)mfp->mf_ffname;
     mfp->mf_ffname = NULL;
   }
 }
@@ -789,7 +789,7 @@ static bool mf_do_open(memfile_T *mfp, char *fname, int flags)
   /// exist yet. If there is a symbolic link, this is most likely an attack.
   FileInfo file_info;
   if ((flags & O_CREAT)
-      && os_fileinfo_link((char *)mfp->mf_fname, &file_info)) {
+      && os_fileinfo_link(mfp->mf_fname, &file_info)) {
     mfp->mf_fd = -1;
     emsg(_("E300: Swap file already exists (symlink attack?)"));
   } else {
diff --git a/src/nvim/memfile_defs.h b/src/nvim/memfile_defs.h
index 537d3e5f65..d1e8fd0fb4 100644
--- a/src/nvim/memfile_defs.h
+++ b/src/nvim/memfile_defs.h
@@ -88,7 +88,7 @@ typedef struct mf_blocknr_trans_item {
 
 /// A memory file.
 typedef struct memfile {
-  char_u *mf_fname;                  /// name of the file
+  char *mf_fname;                    /// name of the file
   char_u *mf_ffname;                 /// idem, full path
   int mf_fd;                         /// file descriptor
   bhdr_T *mf_free_first;             /// first block header in free list
diff --git a/src/nvim/memline.c b/src/nvim/memline.c
index c5e8e3da07..e6cb1b79fc 100644
--- a/src/nvim/memline.c
+++ b/src/nvim/memline.c
@@ -369,7 +369,7 @@ void ml_setname(buf_T *buf)
     if (*dirp == NUL) {             // tried all directories, fail
       break;
     }
-    fname = (char_u *)findswapname(buf, &dirp, (char *)mfp->mf_fname, &found_existing_dir);
+    fname = (char_u *)findswapname(buf, &dirp, mfp->mf_fname, &found_existing_dir);
     // alloc's fname
     if (dirp == NULL) {             // out of memory
       break;
@@ -391,7 +391,7 @@ void ml_setname(buf_T *buf)
     }
 
     // try to rename the swap file
-    if (vim_rename(mfp->mf_fname, fname) == 0) {
+    if (vim_rename((char_u *)mfp->mf_fname, fname) == 0) {
       success = true;
       mf_free_fnames(mfp);
       mf_set_fnames(mfp, (char *)fname);
@@ -402,7 +402,7 @@ void ml_setname(buf_T *buf)
   }
 
   if (mfp->mf_fd == -1) {           // need to (re)open the swap file
-    mfp->mf_fd = os_open((char *)mfp->mf_fname, O_RDWR, 0);
+    mfp->mf_fd = os_open(mfp->mf_fname, O_RDWR, 0);
     if (mfp->mf_fd < 0) {
       // could not (re)open the swap file, what can we do????
       emsg(_("E301: Oops, lost the swap file!!!"));
@@ -445,7 +445,7 @@ void ml_open_file(buf_T *buf)
 
   // For a spell buffer use a temp file name.
   if (buf->b_spell) {
-    fname = vim_tempname();
+    fname = (char_u *)vim_tempname();
     if (fname != NULL) {
       (void)mf_open_file(mfp, (char *)fname);           // consumes fname!
     }
@@ -665,7 +665,7 @@ static void set_b0_fname(ZERO_BL *b0p, buf_T *buf)
 /// not set.
 static void set_b0_dir_flag(ZERO_BL *b0p, buf_T *buf)
 {
-  if (same_directory(buf->b_ml.ml_mfp->mf_fname, (char_u *)buf->b_ffname)) {
+  if (same_directory((char_u *)buf->b_ml.ml_mfp->mf_fname, (char_u *)buf->b_ffname)) {
     b0p->b0_flags |= B0_SAME_DIR;
   } else {
     b0p->b0_flags &= (uint8_t) ~B0_SAME_DIR;
@@ -765,7 +765,7 @@ void ml_recover(bool checkext)
       }
     }
     // get the swap file name that will be used
-    (void)recover_names((char_u *)fname, false, i, (char_u **)&fname_used);
+    (void)recover_names((char_u *)fname, false, i, &fname_used);
   }
   if (fname_used == NULL) {
     goto theend;  // user chose invalid number.
@@ -809,7 +809,7 @@ void ml_recover(bool checkext)
   if ((hp = mf_get(mfp, 0, 1)) == NULL) {
     msg_start();
     msg_puts_attr(_("Unable to read block 0 from "), attr | MSG_HIST);
-    msg_outtrans_attr((char *)mfp->mf_fname, attr | MSG_HIST);
+    msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
     msg_puts_attr(_("\nMaybe no changes were made or Vim did not update the swap file."),
                   attr | MSG_HIST);
     msg_end();
@@ -818,7 +818,7 @@ void ml_recover(bool checkext)
   b0p = hp->bh_data;
   if (STRNCMP(b0p->b0_version, "VIM 3.0", 7) == 0) {
     msg_start();
-    msg_outtrans_attr((char *)mfp->mf_fname, MSG_HIST);
+    msg_outtrans_attr(mfp->mf_fname, MSG_HIST);
     msg_puts_attr(_(" cannot be used with this version of Vim.\n"),
                   MSG_HIST);
     msg_puts_attr(_("Use Vim version 3.0.\n"), MSG_HIST);
@@ -831,7 +831,7 @@ void ml_recover(bool checkext)
   }
   if (b0_magic_wrong(b0p)) {
     msg_start();
-    msg_outtrans_attr((char *)mfp->mf_fname, attr | MSG_HIST);
+    msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
     msg_puts_attr(_(" cannot be used on this computer.\n"),
                   attr | MSG_HIST);
     msg_puts_attr(_("The file was created on "), attr | MSG_HIST);
@@ -851,7 +851,7 @@ void ml_recover(bool checkext)
     mf_new_page_size(mfp, (unsigned)char_to_long(b0p->b0_page_size));
     if (mfp->mf_page_size < previous_page_size) {
       msg_start();
-      msg_outtrans_attr((char *)mfp->mf_fname, attr | MSG_HIST);
+      msg_outtrans_attr(mfp->mf_fname, attr | MSG_HIST);
       msg_puts_attr(_(" has been damaged (page size is smaller than minimum value).\n"),
                     attr | MSG_HIST);
       msg_end();
@@ -880,7 +880,7 @@ void ml_recover(bool checkext)
     }
   }
 
-  home_replace(NULL, (char *)mfp->mf_fname, (char *)NameBuff, MAXPATHL, true);
+  home_replace(NULL, mfp->mf_fname, (char *)NameBuff, MAXPATHL, true);
   smsg(_("Using swap file \"%s\""), NameBuff);
 
   if (buf_spname(curbuf) != NULL) {
@@ -897,7 +897,7 @@ void ml_recover(bool checkext)
   mtime = char_to_long(b0p->b0_mtime);
   if (curbuf->b_ffname != NULL
       && os_fileinfo(curbuf->b_ffname, &org_file_info)
-      && ((os_fileinfo((char *)mfp->mf_fname, &swp_file_info)
+      && ((os_fileinfo(mfp->mf_fname, &swp_file_info)
            && org_file_info.stat.st_mtim.tv_sec
            > swp_file_info.stat.st_mtim.tv_sec)
           || org_file_info.stat.st_mtim.tv_sec != mtime)) {
@@ -1186,7 +1186,7 @@ theend:
 /// @param list  when true, list the swap file names
 /// @param nr  when non-zero, return nr'th swap file name
 /// @param fname_out  result when "nr" > 0
-int recover_names(char_u *fname, int list, int nr, char_u **fname_out)
+int recover_names(char_u *fname, int list, int nr, char **fname_out)
 {
   int num_names;
   char *(names[6]);
@@ -1291,7 +1291,7 @@ int recover_names(char_u *fname, int list, int nr, char_u **fname_out)
 
     // remove swapfile name of the current buffer, it must be ignored
     if (curbuf->b_ml.ml_mfp != NULL
-        && (p = curbuf->b_ml.ml_mfp->mf_fname) != NULL) {
+        && (p = (char_u *)curbuf->b_ml.ml_mfp->mf_fname) != NULL) {
       for (int i = 0; i < num_files; i++) {
         // Do not expand wildcards, on Windows would try to expand
         // "%tmp%" in "%tmp%file"
@@ -1313,7 +1313,7 @@ int recover_names(char_u *fname, int list, int nr, char_u **fname_out)
     if (nr > 0) {
       file_count += num_files;
       if (nr <= file_count) {
-        *fname_out = vim_strsave((char_u *)files[nr - 1 + num_files - file_count]);
+        *fname_out = xstrdup(files[nr - 1 + num_files - file_count]);
         dirp = "";                        // stop searching
       }
     } else if (list) {
@@ -1713,14 +1713,14 @@ theend:
 /// having to check for error everywhere).
 char *ml_get(linenr_T lnum)
 {
-  return (char *)ml_get_buf(curbuf, lnum, false);
+  return ml_get_buf(curbuf, lnum, false);
 }
 
 /// @return  pointer to position "pos".
 char_u *ml_get_pos(const pos_T *pos)
   FUNC_ATTR_NONNULL_ALL
 {
-  return ml_get_buf(curbuf, pos->lnum, false) + pos->col;
+  return (char_u *)ml_get_buf(curbuf, pos->lnum, false) + pos->col;
 }
 
 /// @return  codepoint at pos. pos must be either valid or have col set to MAXCOL!
@@ -1737,14 +1737,14 @@ int gchar_pos(pos_T *pos)
 /// @param will_change  true mark the buffer dirty (chars in the line will be changed)
 ///
 /// @return  a pointer to a line in a specific buffer
-char_u *ml_get_buf(buf_T *buf, linenr_T lnum, bool will_change)
+char *ml_get_buf(buf_T *buf, linenr_T lnum, bool will_change)
   FUNC_ATTR_NONNULL_ALL
 {
   bhdr_T *hp;
   DATA_BL *dp;
-  char_u *ptr;
+  char *ptr;
   static int recursive = 0;
-  static char_u questions[4];
+  static char questions[4];
 
   if (lnum > buf->b_ml.ml_line_count) {  // invalid line number
     if (recursive == 0) {
@@ -1766,7 +1766,7 @@ errorret:
   }
 
   if (buf->b_ml.ml_mfp == NULL) {       // there are no lines
-    return (char_u *)"";
+    return "";
   }
 
   // See if it is the same line as requested last time.
@@ -1795,9 +1795,9 @@ errorret:
 
     dp = hp->bh_data;
 
-    ptr = (char_u *)dp +
+    ptr = (char *)dp +
           ((dp->db_index[lnum - buf->b_ml.ml_locked_low]) & DB_INDEX_MASK);
-    buf->b_ml.ml_line_ptr = ptr;
+    buf->b_ml.ml_line_ptr = (char_u *)ptr;
     buf->b_ml.ml_line_lnum = lnum;
     buf->b_ml.ml_flags &= ~ML_LINE_DIRTY;
   }
@@ -1806,7 +1806,7 @@ errorret:
     ml_add_deleted_len_buf(buf, buf->b_ml.ml_line_ptr, -1);
   }
 
-  return buf->b_ml.ml_line_ptr;
+  return (char *)buf->b_ml.ml_line_ptr;
 }
 
 /// Check if a line that was just obtained by a call to ml_get
@@ -2352,7 +2352,7 @@ int ml_replace_buf(buf_T *buf, linenr_T lnum, char *line, bool copy)
   }
 
   if (readlen && kv_size(buf->update_callbacks)) {
-    ml_add_deleted_len_buf(buf, ml_get_buf(buf, lnum, false), -1);
+    ml_add_deleted_len_buf(buf, (char_u *)ml_get_buf(buf, lnum, false), -1);
   }
 
   buf->b_ml.ml_line_ptr = (char_u *)line;
@@ -3081,7 +3081,7 @@ char_u *makeswapname(char_u *fname, char_u *ffname, buf_T *buf, char_u *dir_name
     return NULL;
   }
 
-  s = get_file_in_dir(r, dir_name);
+  s = (char_u *)get_file_in_dir((char *)r, (char *)dir_name);
   xfree(r);
   return s;
 }
@@ -3098,30 +3098,30 @@ char_u *makeswapname(char_u *fname, char_u *ffname, buf_T *buf, char_u *dir_name
 /// The return value is an allocated string and can be NULL.
 ///
 /// @param dname  don't use "dirname", it is a global for Alpha
-char_u *get_file_in_dir(char_u *fname, char_u *dname)
+char *get_file_in_dir(char *fname, char *dname)
 {
-  char_u *t;
-  char_u *tail;
-  char_u *retval;
+  char *t;
+  char *tail;
+  char *retval;
   int save_char;
 
-  tail = (char_u *)path_tail((char *)fname);
+  tail = path_tail(fname);
 
   if (dname[0] == '.' && dname[1] == NUL) {
-    retval = vim_strsave(fname);
+    retval = xstrdup(fname);
   } else if (dname[0] == '.' && vim_ispathsep(dname[1])) {
     if (tail == fname) {            // no path before file name
-      retval = (char_u *)concat_fnames((char *)dname + 2, (char *)tail, true);
+      retval = concat_fnames(dname + 2, tail, true);
     } else {
-      save_char = *tail;
+      save_char = (uint8_t)(*tail);
       *tail = NUL;
-      t = (char_u *)concat_fnames((char *)fname, (char *)dname + 2, true);
-      *tail = (uint8_t)save_char;
-      retval = (char_u *)concat_fnames((char *)t, (char *)tail, true);
+      t = concat_fnames(fname, dname + 2, true);
+      *tail = (char)save_char;
+      retval = concat_fnames(t, tail, true);
       xfree(t);
     }
   } else {
-    retval = (char_u *)concat_fnames((char *)dname, (char *)tail, true);
+    retval = concat_fnames(dname, tail, true);
   }
 
   return retval;
diff --git a/src/nvim/mouse.c b/src/nvim/mouse.c
index 90084bde17..7b267d6ce4 100644
--- a/src/nvim/mouse.c
+++ b/src/nvim/mouse.c
@@ -631,7 +631,7 @@ colnr_T vcol2col(win_T *const wp, const linenr_T lnum, const colnr_T vcol)
   FUNC_ATTR_NONNULL_ALL FUNC_ATTR_WARN_UNUSED_RESULT
 {
   // try to advance to the specified column
-  char_u *line = ml_get_buf(wp->w_buffer, lnum, false);
+  char_u *line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
   chartabsize_T cts;
   init_chartabsize_arg(&cts, wp, lnum, 0, (char *)line, (char *)line);
   while (cts.cts_vcol < vcol && *cts.cts_ptr != NUL) {
diff --git a/src/nvim/normal.c b/src/nvim/normal.c
index 66038d0c3c..2fe482d8aa 100644
--- a/src/nvim/normal.c
+++ b/src/nvim/normal.c
@@ -629,18 +629,18 @@ static void normal_redraw_mode_message(NormalState *s)
   // If need to redraw, and there is a "keep_msg", redraw before the
   // delay
   if (must_redraw && keep_msg != NULL && !emsg_on_display) {
-    char_u *kmsg;
+    char *kmsg;
 
-    kmsg = (char_u *)keep_msg;
+    kmsg = keep_msg;
     keep_msg = NULL;
     // Showmode() will clear keep_msg, but we want to use it anyway.
     // First update w_topline.
     setcursor();
     update_screen(0);
     // now reset it, otherwise it's put in the history again
-    keep_msg = (char *)kmsg;
+    keep_msg = kmsg;
 
-    kmsg = vim_strsave((char_u *)keep_msg);
+    kmsg = xstrdup(keep_msg);
     msg_attr((const char *)kmsg, keep_msg_attr);
     xfree(kmsg);
   }
@@ -2180,7 +2180,7 @@ bool do_mouse(oparg_T *oap, int c, int dir, long count, bool fixindent)
           find_start_of_word(&VIsual);
           if (*p_sel == 'e' && *get_cursor_pos_ptr() != NUL) {
             curwin->w_cursor.col +=
-              utfc_ptr2len((char *)get_cursor_pos_ptr());
+              utfc_ptr2len(get_cursor_pos_ptr());
           }
           find_end_of_word(&curwin->w_cursor);
         }
@@ -2416,7 +2416,7 @@ size_t find_ident_at_pos(win_T *wp, linenr_T lnum, colnr_T startcol, char **text
 
   // if i == 0: try to find an identifier
   // if i == 1: try to find any non-white text
-  char_u *ptr = ml_get_buf(wp->w_buffer, lnum, false);
+  char_u *ptr = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
   for (i = (find_type & FIND_IDENT) ? 0 : 1; i < 2; i++) {
     // 1. skip to start of identifier/text
     col = startcol;
@@ -2675,9 +2675,9 @@ void clear_showcmd(void)
 
       if (cursor_bot) {
         s = ml_get_pos(&VIsual);
-        e = get_cursor_pos_ptr();
+        e = (char_u *)get_cursor_pos_ptr();
       } else {
-        s = get_cursor_pos_ptr();
+        s = (char_u *)get_cursor_pos_ptr();
         e = ml_get_pos(&VIsual);
       }
       while ((*p_sel != 'e') ? s <= e : s < e) {
@@ -3361,7 +3361,7 @@ static bool nv_screengo(oparg_T *oap, int dir, long dist)
       virtcol -= vim_strsize((char *)get_showbreak_value(curwin));
     }
 
-    int c = utf_ptr2char((char *)get_cursor_pos_ptr());
+    int c = utf_ptr2char(get_cursor_pos_ptr());
     if (dir == FORWARD && virtcol < curwin->w_curswant
         && (curwin->w_curswant <= (colnr_T)width1)
         && !vim_isprintc(c) && c > 255) {
@@ -4451,7 +4451,7 @@ bool get_visual_text(cmdarg_T *cap, char **pp, size_t *lenp)
 static void nv_tagpop(cmdarg_T *cap)
 {
   if (!checkclearopq(cap->oap)) {
-    do_tag((char_u *)"", DT_POP, (int)cap->count1, false, true);
+    do_tag("", DT_POP, (int)cap->count1, false, true);
   }
 }
 
@@ -4600,7 +4600,7 @@ static void nv_right(cmdarg_T *cap)
       if (virtual_active()) {
         oneright();
       } else {
-        curwin->w_cursor.col += utfc_ptr2len((char *)get_cursor_pos_ptr());
+        curwin->w_cursor.col += utfc_ptr2len(get_cursor_pos_ptr());
       }
     }
   }
@@ -4648,7 +4648,7 @@ static void nv_left(cmdarg_T *cap)
         // Don't adjust op_end now, otherwise it won't work.
         if ((cap->oap->op_type == OP_DELETE || cap->oap->op_type == OP_CHANGE)
             && !LINEEMPTY(curwin->w_cursor.lnum)) {
-          char_u *cp = get_cursor_pos_ptr();
+          char_u *cp = (char_u *)get_cursor_pos_ptr();
 
           if (*cp != NUL) {
             curwin->w_cursor.col += utfc_ptr2len((char *)cp);
@@ -5360,7 +5360,7 @@ static void nv_replace(cmdarg_T *cap)
   }
 
   // Abort if not enough characters to replace.
-  ptr = get_cursor_pos_ptr();
+  ptr = (char_u *)get_cursor_pos_ptr();
   if (STRLEN(ptr) < (unsigned)cap->count1
       || (mb_charlen(ptr) < cap->count1)) {
     clearopbeep(cap->oap);
diff --git a/src/nvim/ops.c b/src/nvim/ops.c
index 5d505f41a2..10e957287e 100644
--- a/src/nvim/ops.c
+++ b/src/nvim/ops.c
@@ -722,26 +722,26 @@ int get_expr_register(void)
   if (*new_line == NUL) {  // use previous line
     xfree(new_line);
   } else {
-    set_expr_line(new_line);
+    set_expr_line((char *)new_line);
   }
   return '=';
 }
 
 /// Set the expression for the '=' register.
 /// Argument must be an allocated string.
-void set_expr_line(char_u *new_line)
+void set_expr_line(char *new_line)
 {
   xfree(expr_line);
-  expr_line = new_line;
+  expr_line = (char_u *)new_line;
 }
 
 /// Get the result of the '=' register expression.
 ///
 /// @return  a pointer to allocated memory, or NULL for failure.
-char_u *get_expr_line(void)
+char *get_expr_line(void)
 {
-  char_u *expr_copy;
-  char_u *rv;
+  char *expr_copy;
+  char *rv;
   static int nested = 0;
 
   if (expr_line == NULL) {
@@ -750,7 +750,7 @@ char_u *get_expr_line(void)
 
   // Make a copy of the expression, because evaluating it may cause it to be
   // changed.
-  expr_copy = vim_strsave(expr_line);
+  expr_copy = xstrdup((char *)expr_line);
 
   // When we are invoked recursively limit the evaluation to 10 levels.
   // Then return the string as-is.
@@ -759,19 +759,19 @@ char_u *get_expr_line(void)
   }
 
   nested++;
-  rv = (char_u *)eval_to_string((char *)expr_copy, NULL, true);
+  rv = eval_to_string(expr_copy, NULL, true);
   nested--;
   xfree(expr_copy);
   return rv;
 }
 
 /// Get the '=' register expression itself, without evaluating it.
-char_u *get_expr_line_src(void)
+char *get_expr_line_src(void)
 {
   if (expr_line == NULL) {
     return NULL;
   }
-  return vim_strsave(expr_line);
+  return xstrdup((char *)expr_line);
 }
 
 /// @return  whether `regname` is a valid name of a yank register.
@@ -1070,11 +1070,11 @@ static char_u *execreg_line_continuation(char **lines, size_t *idx)
     }
   }
   ga_append(&ga, NUL);
-  char_u *str = vim_strsave(ga.ga_data);
+  char *str = xstrdup(ga.ga_data);
   ga_clear(&ga);
 
   *idx = i;
-  return str;
+  return (char_u *)str;
 }
 
 /// Execute a yank register: copy it into the stuff buffer
@@ -1130,7 +1130,7 @@ int do_execreg(int regname, int colon, int addcr, int silent)
     }
     xfree(p);
   } else if (regname == '=') {
-    p = get_expr_line();
+    p = (char_u *)get_expr_line();
     if (p == NULL) {
       return FAIL;
     }
@@ -1338,7 +1338,7 @@ bool get_spec_reg(int regname, char **argp, bool *allocated, bool errmsg)
     return true;
 
   case '=':                     // result of expression
-    *argp = (char *)get_expr_line();
+    *argp = get_expr_line();
     *allocated = true;
     return true;
 
@@ -1392,7 +1392,7 @@ bool get_spec_reg(int regname, char **argp, bool *allocated, bool errmsg)
       return false;
     }
 
-    *argp = (char *)ml_get_buf(curwin->w_buffer, curwin->w_cursor.lnum, false);
+    *argp = ml_get_buf(curwin->w_buffer, curwin->w_cursor.lnum, false);
     return true;
 
   case '_':                     // black hole: always empty
@@ -1801,7 +1801,7 @@ static void mb_adjust_opend(oparg_T *oap)
 static inline void pbyte(pos_T lp, int c)
 {
   assert(c <= UCHAR_MAX);
-  *(ml_get_buf(curbuf, lp.lnum, true) + lp.col) = (char_u)c;
+  *(ml_get_buf(curbuf, lp.lnum, true) + lp.col) = (char)c;
   if (!curbuf_splice_pending) {
     extmark_splice_cols(curbuf, (int)lp.lnum - 1, lp.col, 1, 1, kExtmarkUndo);
   }
@@ -1978,7 +1978,7 @@ static int op_replace(oparg_T *oap, int c)
       n = gchar_cursor();
       if (n != NUL) {
         int new_byte_len = utf_char2len(c);
-        int old_byte_len = utfc_ptr2len((char *)get_cursor_pos_ptr());
+        int old_byte_len = utfc_ptr2len(get_cursor_pos_ptr());
 
         if (new_byte_len > 1 || old_byte_len > 1) {
           // This is slow, but it handles replacing a single-byte
@@ -2199,7 +2199,7 @@ bool swapchar(int op_type, pos_T *pos)
 
       curwin->w_cursor = *pos;
       // don't use del_char(), it also removes composing chars
-      del_bytes(utf_ptr2len((char *)get_cursor_pos_ptr()), false, false);
+      del_bytes(utf_ptr2len(get_cursor_pos_ptr()), false, false);
       ins_char(nc);
       curwin->w_cursor = sp;
     } else {
@@ -2995,7 +2995,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
         // STRLEN(ml_get(curwin->w_cursor.lnum)). With 'virtualedit' and the
         // cursor past the end of the line, curwin->w_cursor.coladd is
         // incremented instead of curwin->w_cursor.col.
-        char_u *cursor_pos = get_cursor_pos_ptr();
+        char_u *cursor_pos = (char_u *)get_cursor_pos_ptr();
         bool one_past_line = (*cursor_pos == NUL);
         bool eol = false;
         if (!one_past_line) {
@@ -3101,7 +3101,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
       if (u_save_cursor() == FAIL) {
         goto end;
       }
-      char *p = (char *)get_cursor_pos_ptr();
+      char *p = get_cursor_pos_ptr();
       if (dir == FORWARD && *p != NUL) {
         MB_PTR_ADV(p);
       }
@@ -3210,7 +3210,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
       }
 
       // move to start of next multi-byte character
-      curwin->w_cursor.col += utfc_ptr2len((char *)get_cursor_pos_ptr());
+      curwin->w_cursor.col += utfc_ptr2len(get_cursor_pos_ptr());
       col++;
     } else {
       getvcol(curwin, &curwin->w_cursor, &col, NULL, &endcol2);
@@ -3393,7 +3393,7 @@ void do_put(int regname, yankreg_T *reg, int dir, long count, int flags)
       // if type is kMTCharWise, FORWARD is the same as BACKWARD on the next
       // char
       if (dir == FORWARD && gchar_cursor() != NUL) {
-        int bytelen = utfc_ptr2len((char *)get_cursor_pos_ptr());
+        int bytelen = utfc_ptr2len(get_cursor_pos_ptr());
 
         // put it on the next of the multi-byte character.
         col += bytelen;
@@ -4853,13 +4853,13 @@ void format_reg_type(MotionType reg_type, colnr_T reg_width, char *buf, size_t b
 /// Otherwise just return `s`.
 ///
 /// @return  a void * for use in get_reg_contents().
-static void *get_reg_wrap_one_line(char_u *s, int flags)
+static void *get_reg_wrap_one_line(char *s, int flags)
 {
   if (!(flags & kGRegList)) {
     return s;
   }
   list_T *const list = tv_list_alloc(1);
-  tv_list_append_allocated_string(list, (char *)s);
+  tv_list_append_allocated_string(list, s);
   return list;
 }
 
@@ -4901,9 +4901,9 @@ void *get_reg_contents(int regname, int flags)
       return NULL;
     }
     if (allocated) {
-      return get_reg_wrap_one_line((char_u *)retval, flags);
+      return get_reg_wrap_one_line(retval, flags);
     }
-    return get_reg_wrap_one_line(vim_strsave((char_u *)retval), flags);
+    return get_reg_wrap_one_line(xstrdup(retval), flags);
   }
 
   yankreg_T *reg = get_yank_register(regname, YREG_PASTE);
@@ -5574,7 +5574,7 @@ static Callback opfunc_cb;
 /// @return  OK or FAIL
 int set_operatorfunc_option(void)
 {
-  return option_set_callback_func((char_u *)p_opfunc, &opfunc_cb);
+  return option_set_callback_func(p_opfunc, &opfunc_cb);
 }
 
 #if defined(EXITFREE)
diff --git a/src/nvim/option.c b/src/nvim/option.c
index 12c2888f5c..e54e6080f0 100644
--- a/src/nvim/option.c
+++ b/src/nvim/option.c
@@ -420,7 +420,7 @@ void set_init_1(bool clean_arg)
     // use utf-8 as 'default' if locale encoding can't be detected.
     p = (char_u *)xmemdupz(S_LEN("utf-8"));
   }
-  fenc_default = p;
+  fenc_default = (char *)p;
 
 #ifdef HAVE_WORKING_LIBINTL
   // GNU gettext 0.10.37 supports this feature: set the codeset used for
@@ -1129,9 +1129,9 @@ int do_set(char *arg, int opt_flags)
                                     opt_flags);
           } else if (opt_idx >= 0) {  // String.
             char_u *save_arg = NULL;
-            char_u *s = NULL;
+            char *s = NULL;
             char_u *oldval = NULL;         // previous value if *varp
-            char_u *newval;
+            char *newval;
             char_u *origval = NULL;
             char_u *origval_l = NULL;
             char_u *origval_g = NULL;
@@ -1175,24 +1175,24 @@ int do_set(char *arg, int opt_flags)
             }
 
             if (nextchar == '&') {  // set to default val
-              newval = options[opt_idx].def_val;
+              newval = (char *)options[opt_idx].def_val;
               // expand environment variables and ~ since the
               // default value was already expanded, only
               // required when an environment variable was set
               // later
               if (newval == NULL) {
-                newval = (char_u *)empty_option;
+                newval = empty_option;
               } else if (!(options[opt_idx].flags & P_NO_DEF_EXP)) {
-                s = option_expand(opt_idx, newval);
+                s = (char *)option_expand(opt_idx, (char_u *)newval);
                 if (s == NULL) {
                   s = newval;
                 }
-                newval = vim_strsave(s);
+                newval = xstrdup(s);
               } else {
-                newval = (char_u *)xstrdup((char *)newval);
+                newval = xstrdup(newval);
               }
             } else if (nextchar == '<') {  // set to global val
-              newval = vim_strsave(*(char_u **)get_varp_scope(&(options[opt_idx]), OPT_GLOBAL));
+              newval = xstrdup(*(char **)get_varp_scope(&(options[opt_idx]), OPT_GLOBAL));
             } else {
               arg++;                    // jump to after the '=' or ':'
 
@@ -1212,13 +1212,13 @@ int do_set(char *arg, int opt_flags)
                   *(char **)varp = empty_option;
                   break;
                 case 1:
-                  *(char_u **)varp = vim_strsave((char_u *)"indent,eol");
+                  *(char_u **)varp = (char_u *)xstrdup("indent,eol");
                   break;
                 case 2:
-                  *(char_u **)varp = vim_strsave((char_u *)"indent,eol,start");
+                  *(char_u **)varp = (char_u *)xstrdup("indent,eol,start");
                   break;
                 case 3:
-                  *(char_u **)varp = vim_strsave((char_u *)"indent,eol,nostop");
+                  *(char_u **)varp = (char_u *)xstrdup("indent,eol,nostop");
                   break;
                 }
                 xfree(oldval);
@@ -1301,7 +1301,7 @@ int do_set(char *arg, int opt_flags)
                   arg += i;
                   s += i;
                 } else {
-                  *s++ = (uint8_t)(*arg++);
+                  *s++ = *arg++;
                 }
               }
               *s = NUL;
@@ -1311,7 +1311,7 @@ int do_set(char *arg, int opt_flags)
               // comma.
               if (!(adding || prepending || removing)
                   || (flags & P_COMMA)) {
-                s = option_expand(opt_idx, newval);
+                s = (char *)option_expand(opt_idx, (char_u *)newval);
                 if (s != NULL) {
                   xfree(newval);
                   newlen = (unsigned)STRLEN(s) + 1;
@@ -1328,7 +1328,7 @@ int do_set(char *arg, int opt_flags)
               i = 0;                    // init for GCC
               if (removing || (flags & P_NODUP)) {
                 i = (int)STRLEN(newval);
-                s = find_dup_item(origval, newval, flags);
+                s = (char *)find_dup_item(origval, (char_u *)newval, flags);
 
                 // do not add if already there
                 if ((adding || prepending) && s != NULL) {
@@ -1340,7 +1340,7 @@ int do_set(char *arg, int opt_flags)
                 // if no duplicate, move pointer to end of
                 // original value
                 if (s == NULL) {
-                  s = origval + (int)STRLEN(origval);
+                  s = (char *)origval + (int)STRLEN(origval);
                 }
               }
 
@@ -1377,7 +1377,7 @@ int do_set(char *arg, int opt_flags)
                 if (*s) {
                   // may need to remove a comma
                   if (flags & P_COMMA) {
-                    if (s == origval) {
+                    if (s == (char *)origval) {
                       // include comma after string
                       if (s[i] == ',') {
                         i++;
@@ -1388,7 +1388,7 @@ int do_set(char *arg, int opt_flags)
                       i++;
                     }
                   }
-                  STRMOVE(newval + (s - origval), s + i);
+                  STRMOVE(newval + (s - (char *)origval), s + i);
                 }
               }
 
@@ -1399,14 +1399,14 @@ int do_set(char *arg, int opt_flags)
                   // 'whichwrap'
                   if (flags & P_ONECOMMA) {
                     if (*s != ',' && *(s + 1) == ','
-                        && vim_strchr((char *)s + 2, *s) != NULL) {
+                        && vim_strchr(s + 2, *s) != NULL) {
                       // Remove the duplicated value and the next comma.
                       STRMOVE(s, s + 2);
                       continue;
                     }
                   } else {
                     if ((!(flags & P_COMMA) || *s != ',')
-                        && vim_strchr((char *)s + 1, *s) != NULL) {
+                        && vim_strchr(s + 1, *s) != NULL) {
                       STRMOVE(s, s + 1);
                       continue;
                     }
@@ -1421,7 +1421,7 @@ int do_set(char *arg, int opt_flags)
             }
 
             // Set the new value.
-            *(char_u **)(varp) = newval;
+            *(char_u **)(varp) = (char_u *)newval;
 
             // origval may be freed by
             // did_set_string_option(), make a copy.
@@ -1431,7 +1431,7 @@ int do_set(char *arg, int opt_flags)
 
             // newval (and varp) may become invalid if the
             // buffer is closed by autocommands.
-            saved_newval = (newval != NULL) ? xstrdup((char *)newval) : 0;
+            saved_newval = (newval != NULL) ? xstrdup(newval) : 0;
 
             {
               uint32_t *p = insecure_flag(curwin, opt_idx, opt_flags);
@@ -4451,7 +4451,7 @@ void buf_copy_options(buf_T *buf, int flags)
       buf->b_p_cpt = xstrdup(p_cpt);
       COPY_OPT_SCTX(buf, BV_CPT);
 #ifdef BACKSLASH_IN_FILENAME
-      buf->b_p_csl = vim_strsave(p_csl);
+      buf->b_p_csl = xstrdup(p_csl);
       COPY_OPT_SCTX(buf, BV_CSL);
 #endif
       buf->b_p_cfu = xstrdup(p_cfu);
@@ -4826,7 +4826,7 @@ int ExpandSettings(expand_T *xp, regmatch_T *regmatch, int *num_file, char ***fi
   int num_normal = 0;  // Nr of matching non-term-code settings
   int match;
   int count = 0;
-  char_u *str;
+  char *str;
   int loop;
   static char *(names[]) = { "all" };
   int ic = regmatch->rm_ic;  // remember the ignore-case flag
@@ -4848,7 +4848,7 @@ int ExpandSettings(expand_T *xp, regmatch_T *regmatch, int *num_file, char ***fi
         }
       }
     }
-    for (size_t opt_idx = 0; (str = (char_u *)options[opt_idx].fullname) != NULL;
+    for (size_t opt_idx = 0; (str = options[opt_idx].fullname) != NULL;
          opt_idx++) {
       if (options[opt_idx].var == NULL) {
         continue;
@@ -4858,7 +4858,7 @@ int ExpandSettings(expand_T *xp, regmatch_T *regmatch, int *num_file, char ***fi
         continue;
       }
       match = false;
-      if (vim_regexec(regmatch, (char *)str, (colnr_T)0)
+      if (vim_regexec(regmatch, str, (colnr_T)0)
           || (options[opt_idx].shortname != NULL
               && vim_regexec(regmatch,
                              options[opt_idx].shortname,
@@ -4870,7 +4870,7 @@ int ExpandSettings(expand_T *xp, regmatch_T *regmatch, int *num_file, char ***fi
         if (loop == 0) {
           num_normal++;
         } else {
-          (*file)[count++] = (char *)vim_strsave(str);
+          (*file)[count++] = xstrdup(str);
         }
       }
     }
@@ -4881,7 +4881,7 @@ int ExpandSettings(expand_T *xp, regmatch_T *regmatch, int *num_file, char ***fi
       } else {
         return OK;
       }
-      *file = xmalloc((size_t)(*num_file) * sizeof(char_u *));
+      *file = xmalloc((size_t)(*num_file) * sizeof(char *));
     }
   }
   return OK;
@@ -5230,7 +5230,7 @@ int fill_culopt_flags(char *val, win_T *wp)
 /// Set the callback function value for an option that accepts a function name,
 /// lambda, et al. (e.g. 'operatorfunc', 'tagfunc', etc.)
 /// @return  OK if the option is successfully set to a function, otherwise FAIL
-int option_set_callback_func(char_u *optval, Callback *optcb)
+int option_set_callback_func(char *optval, Callback *optcb)
 {
   if (optval == NULL || *optval == NUL) {
     callback_free(optcb);
@@ -5242,7 +5242,7 @@ int option_set_callback_func(char_u *optval, Callback *optcb)
       || (STRNCMP(optval, "function(", 9) == 0)
       || (STRNCMP(optval, "funcref(", 8) == 0)) {
     // Lambda expression or a funcref
-    tv = eval_expr((char *)optval);
+    tv = eval_expr(optval);
     if (tv == NULL) {
       return FAIL;
     }
@@ -5250,7 +5250,7 @@ int option_set_callback_func(char_u *optval, Callback *optcb)
     // treat everything else as a function name string
     tv = xcalloc(1, sizeof(*tv));
     tv->v_type = VAR_STRING;
-    tv->vval.v_string = (char *)vim_strsave(optval);
+    tv->vval.v_string = xstrdup(optval);
   }
 
   Callback cb;
diff --git a/src/nvim/optionstr.c b/src/nvim/optionstr.c
index c226966ef6..8581dae7a3 100644
--- a/src/nvim/optionstr.c
+++ b/src/nvim/optionstr.c
@@ -253,7 +253,7 @@ void check_buf_options(buf_T *buf)
 
 /// Free the string allocated for an option.
 /// Checks for the string being empty_option. This may happen if we're out of
-/// memory, vim_strsave() returned NULL, which was replaced by empty_option by
+/// memory, xstrdup() returned NULL, which was replaced by empty_option by
 /// check_options().
 /// Does NOT check for P_ALLOCED flag!
 void free_string_option(char *p)
diff --git a/src/nvim/os/env.c b/src/nvim/os/env.c
index c940c86675..2f2a8c7fdc 100644
--- a/src/nvim/os/env.c
+++ b/src/nvim/os/env.c
@@ -669,8 +669,8 @@ void expand_env_esc(char_u *restrict srcp, char_u *restrict dst, int dstlen, boo
 
           ExpandInit(&xpc);
           xpc.xp_context = EXPAND_FILES;
-          var = ExpandOne(&xpc, dst, NULL,
-                          WILD_ADD_SLASH|WILD_SILENT, WILD_EXPAND_FREE);
+          var = (char_u *)ExpandOne(&xpc, (char *)dst, NULL,
+                                    WILD_ADD_SLASH|WILD_SILENT, WILD_EXPAND_FREE);
           mustfree = true;
         }
 #else
@@ -684,7 +684,7 @@ void expand_env_esc(char_u *restrict srcp, char_u *restrict dst, int dstlen, boo
       // If 'shellslash' is set change backslashes to forward slashes.
       // Can't use slash_adjust(), p_ssl may be set temporarily.
       if (p_ssl && var != NULL && vim_strchr(var, '\\') != NULL) {
-        char_u *p = vim_strsave(var);
+        char_u *p = xstrdup(var);
 
         if (mustfree) {
           xfree(var);
diff --git a/src/nvim/os/shell.c b/src/nvim/os/shell.c
index f3b3c1dfbf..25f51f89a9 100644
--- a/src/nvim/os/shell.c
+++ b/src/nvim/os/shell.c
@@ -52,11 +52,11 @@ static void save_patterns(int num_pat, char **pat, int *num_file, char ***file)
 {
   *file = xmalloc((size_t)num_pat * sizeof(char_u *));
   for (int i = 0; i < num_pat; i++) {
-    char_u *s = vim_strsave((char_u *)pat[i]);
+    char *s = xstrdup(pat[i]);
     // Be compatible with expand_filename(): halve the number of
     // backslashes.
-    backslash_halve((char *)s);
-    (*file)[i] = (char *)s;
+    backslash_halve(s);
+    (*file)[i] = s;
   }
   *num_file = num_pat;
 }
@@ -160,7 +160,7 @@ int os_expand_wildcards(int num_pat, char **pat, int *num_file, char ***file, in
   }
 
   // get a name for the temp file
-  if ((tempname = vim_tempname()) == NULL) {
+  if ((tempname = (char_u *)vim_tempname()) == NULL) {
     emsg(_(e_notmp));
     return FAIL;
   }
@@ -746,7 +746,7 @@ char_u *get_cmd_output(char_u *cmd, char_u *infile, ShellOpts flags, size_t *ret
   }
 
   // get a name for the temp file
-  char_u *tempname = vim_tempname();
+  char_u *tempname = (char_u *)vim_tempname();
   if (tempname == NULL) {
     emsg(_(e_notmp));
     return NULL;
diff --git a/src/nvim/path.c b/src/nvim/path.c
index 2646b9e75e..accd7badbb 100644
--- a/src/nvim/path.c
+++ b/src/nvim/path.c
@@ -829,10 +829,10 @@ static bool is_unique(char_u *maybe_unique, garray_T *gap, int i)
 static void expand_path_option(char_u *curdir, garray_T *gap)
 {
   char_u *path_option = *curbuf->b_p_path == NUL ? p_path : (char_u *)curbuf->b_p_path;
-  char_u *buf = xmalloc(MAXPATHL);
+  char *buf = xmalloc(MAXPATHL);
 
   while (*path_option != NUL) {
-    copy_option_part((char **)&path_option, (char *)buf, MAXPATHL, " ,");
+    copy_option_part((char **)&path_option, buf, MAXPATHL, " ,");
 
     if (buf[0] == '.' && (buf[1] == NUL || vim_ispathsep(buf[1]))) {
       // Relative to current buffer:
@@ -852,12 +852,12 @@ static void expand_path_option(char_u *curdir, garray_T *gap)
         STRMOVE(buf + len, buf + 2);
       }
       memmove(buf, curbuf->b_ffname, len);
-      simplify_filename(buf);
+      simplify_filename((char_u *)buf);
     } else if (buf[0] == NUL) {
       STRCPY(buf, curdir);  // relative to current directory
-    } else if (path_with_url((char *)buf)) {
+    } else if (path_with_url(buf)) {
       continue;  // URL can't be used here
-    } else if (!path_is_absolute(buf)) {
+    } else if (!path_is_absolute((char_u *)buf)) {
       // Expand relative path to their full path equivalent
       size_t len = STRLEN(curdir);
       if (len + STRLEN(buf) + 3 > MAXPATHL) {
@@ -866,10 +866,10 @@ static void expand_path_option(char_u *curdir, garray_T *gap)
       STRMOVE(buf + len + 1, buf);
       STRCPY(buf, curdir);
       buf[len] = (char_u)PATHSEP;
-      simplify_filename(buf);
+      simplify_filename((char_u *)buf);
     }
 
-    GA_APPEND(char_u *, gap, vim_strsave(buf));
+    GA_APPEND(char *, gap, xstrdup(buf));
   }
 
   xfree(buf);
@@ -919,12 +919,12 @@ static char_u *get_path_cutoff(char_u *fname, garray_T *gap)
 // that matches the pattern. Beware, this is at least O(n^2) wrt "gap->ga_len".
 static void uniquefy_paths(garray_T *gap, char_u *pattern)
 {
-  char_u **fnames = (char_u **)gap->ga_data;
+  char **fnames = gap->ga_data;
   bool sort_again = false;
   regmatch_T regmatch;
   garray_T path_ga;
-  char_u **in_curdir = NULL;
-  char_u *short_name;
+  char **in_curdir = NULL;
+  char *short_name;
 
   ga_remove_duplicate_strings(gap);
   ga_init(&path_ga, (int)sizeof(char_u *), 1);
@@ -933,11 +933,11 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
   // regex matches anywhere in the path. FIXME: is this valid for all
   // possible patterns?
   size_t len = STRLEN(pattern);
-  char_u *file_pattern = xmalloc(len + 2);
+  char *file_pattern = xmalloc(len + 2);
   file_pattern[0] = '*';
   file_pattern[1] = NUL;
   STRCAT(file_pattern, pattern);
-  char *pat = file_pat_to_reg_pat((char *)file_pattern, NULL, NULL, true);
+  char *pat = file_pat_to_reg_pat(file_pattern, NULL, NULL, true);
   xfree(file_pattern);
   if (pat == NULL) {
     return;
@@ -957,21 +957,21 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
   in_curdir = xcalloc((size_t)gap->ga_len, sizeof(char_u *));
 
   for (int i = 0; i < gap->ga_len && !got_int; i++) {
-    char_u *path = fnames[i];
+    char *path = fnames[i];
     int is_in_curdir;
-    char_u *dir_end = (char_u *)gettail_dir((const char *)path);
-    char_u *pathsep_p;
-    char_u *path_cutoff;
+    char *dir_end = (char *)gettail_dir((const char *)path);
+    char *pathsep_p;
+    char *path_cutoff;
 
     len = STRLEN(path);
     is_in_curdir = FNAMENCMP(curdir, path, dir_end - path) == 0
                    && curdir[dir_end - path] == NUL;
     if (is_in_curdir) {
-      in_curdir[i] = vim_strsave(path);
+      in_curdir[i] = xstrdup(path);
     }
 
     // Shorten the filename while maintaining its uniqueness
-    path_cutoff = get_path_cutoff(path, &path_ga);
+    path_cutoff = (char *)get_path_cutoff((char_u *)path, &path_ga);
 
     // Don't assume all files can be reached without path when search
     // pattern starts with **/, so only remove path_cutoff
@@ -979,17 +979,17 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
     if (pattern[0] == '*' && pattern[1] == '*'
         && vim_ispathsep_nocolon(pattern[2])
         && path_cutoff != NULL
-        && vim_regexec(&regmatch, (char *)path_cutoff, (colnr_T)0)
-        && is_unique(path_cutoff, gap, i)) {
+        && vim_regexec(&regmatch, path_cutoff, (colnr_T)0)
+        && is_unique((char_u *)path_cutoff, gap, i)) {
       sort_again = true;
       memmove(path, path_cutoff, STRLEN(path_cutoff) + 1);
     } else {
       // Here all files can be reached without path, so get shortest
       // unique path.  We start at the end of the path. */
       pathsep_p = path + len - 1;
-      while (find_previous_pathsep(path, &pathsep_p)) {
-        if (vim_regexec(&regmatch, (char *)pathsep_p + 1, (colnr_T)0)
-            && is_unique(pathsep_p + 1, gap, i)
+      while (find_previous_pathsep((char_u *)path, (char_u **)&pathsep_p)) {
+        if (vim_regexec(&regmatch, pathsep_p + 1, (colnr_T)0)
+            && is_unique((char_u *)pathsep_p + 1, gap, i)
             && path_cutoff != NULL && pathsep_p + 1 >= path_cutoff) {
           sort_again = true;
           memmove(path, pathsep_p + 1, STRLEN(pathsep_p));
@@ -998,7 +998,7 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
       }
     }
 
-    if (path_is_absolute(path)) {
+    if (path_is_absolute((char_u *)path)) {
       // Last resort: shorten relative to curdir if possible.
       // 'possible' means:
       // 1. It is under the current directory.
@@ -1009,10 +1009,10 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
       //     c:\foo\bar\file.txt   c:\foo\bar    .\file.txt
       //     /file.txt             /             /file.txt
       //     c:\file.txt           c:\           .\file.txt
-      short_name = path_shorten_fname(path, curdir);
+      short_name = (char *)path_shorten_fname((char_u *)path, curdir);
       if (short_name != NULL && short_name > path + 1) {
         STRCPY(path, ".");
-        add_pathsep((char *)path);
+        add_pathsep(path);
         STRMOVE(path + STRLEN(path), short_name);
       }
     }
@@ -1021,8 +1021,8 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
 
   // Shorten filenames in /in/current/directory/{filename}
   for (int i = 0; i < gap->ga_len && !got_int; i++) {
-    char_u *rel_path;
-    char_u *path = in_curdir[i];
+    char *rel_path;
+    char *path = in_curdir[i];
 
     if (path == NULL) {
       continue;
@@ -1030,18 +1030,18 @@ static void uniquefy_paths(garray_T *gap, char_u *pattern)
 
     // If the {filename} is not unique, change it to ./{filename}.
     // Else reduce it to {filename}
-    short_name = path_shorten_fname(path, curdir);
+    short_name = (char *)path_shorten_fname((char_u *)path, curdir);
     if (short_name == NULL) {
       short_name = path;
     }
-    if (is_unique(short_name, gap, i)) {
+    if (is_unique((char_u *)short_name, gap, i)) {
       STRCPY(fnames[i], short_name);
       continue;
     }
 
     rel_path = xmalloc(STRLEN(short_name) + STRLEN(PATHSEPSTR) + 2);
     STRCPY(rel_path, ".");
-    add_pathsep((char *)rel_path);
+    add_pathsep(rel_path);
     STRCAT(rel_path, short_name);
 
     xfree(fnames[i]);
@@ -2099,11 +2099,11 @@ char_u *path_shorten_fname(char_u *full_path, char_u *dir_name)
 ///                        If FAIL is returned, *num_file and *file are either
 ///                        unchanged or *num_file is set to 0 and *file is set
 ///                        to NULL or points to "".
-int expand_wildcards_eval(char_u **pat, int *num_file, char ***file, int flags)
+int expand_wildcards_eval(char **pat, int *num_file, char ***file, int flags)
 {
   int ret = FAIL;
-  char_u *eval_pat = NULL;
-  char *exp_pat = (char *)(*pat);
+  char *eval_pat = NULL;
+  char *exp_pat = *pat;
   char *ignored_msg;
   size_t usedlen;
   const bool is_cur_alt_file = *exp_pat == '%' || *exp_pat == '#';
@@ -2111,12 +2111,13 @@ int expand_wildcards_eval(char_u **pat, int *num_file, char ***file, int flags)
 
   if (is_cur_alt_file || *exp_pat == '<') {
     emsg_off++;
-    eval_pat = eval_vars((char_u *)exp_pat, (char_u *)exp_pat, &usedlen, NULL, &ignored_msg, NULL,
-                         true);
+    eval_pat = (char *)eval_vars((char_u *)exp_pat, (char_u *)exp_pat, &usedlen, NULL, &ignored_msg,
+                                 NULL,
+                                 true);
     emsg_off--;
     if (eval_pat != NULL) {
       star_follows = strcmp(exp_pat + usedlen, "*") == 0;
-      exp_pat = concat_str((char *)eval_pat, exp_pat + usedlen);
+      exp_pat = concat_str(eval_pat, exp_pat + usedlen);
     }
   }
 
@@ -2130,7 +2131,7 @@ int expand_wildcards_eval(char_u **pat, int *num_file, char ***file, int flags)
       // pattern anyway (without the star) so that this works for remote
       // files and non-file buffer names.
       *file = xmalloc(sizeof(char *));
-      **file = (char *)eval_pat;
+      **file = eval_pat;
       eval_pat = NULL;
       *num_file = 1;
       ret = OK;
diff --git a/src/nvim/plines.c b/src/nvim/plines.c
index 3ba09b45a1..c676dcddbd 100644
--- a/src/nvim/plines.c
+++ b/src/nvim/plines.c
@@ -102,7 +102,7 @@ int plines_win_nofold(win_T *wp, linenr_T lnum)
   unsigned int col;
   int width;
 
-  s = (char *)ml_get_buf(wp->w_buffer, lnum, false);
+  s = ml_get_buf(wp->w_buffer, lnum, false);
   if (*s == NUL) {  // empty line
     return 1;
   }
@@ -144,7 +144,7 @@ int plines_win_col(win_T *wp, linenr_T lnum, long column)
     return lines + 1;
   }
 
-  char_u *line = ml_get_buf(wp->w_buffer, lnum, false);
+  char_u *line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
 
   colnr_T col = 0;
   chartabsize_T cts;
diff --git a/src/nvim/quickfix.c b/src/nvim/quickfix.c
index 86f60cb57e..cd2dd4b89c 100644
--- a/src/nvim/quickfix.c
+++ b/src/nvim/quickfix.c
@@ -710,7 +710,7 @@ static int qf_get_next_buf_line(qfstate_T *state)
   if (state->buflnum > state->lnumlast) {
     return QF_END_OF_INPUT;
   }
-  char *p_buf = (char *)ml_get_buf(state->buf, state->buflnum, false);
+  char *p_buf = ml_get_buf(state->buf, state->buflnum, false);
   state->buflnum += 1;
 
   size_t len = STRLEN(p_buf);
@@ -3832,7 +3832,7 @@ static buf_T *qf_find_buf(qf_info_T *qi)
 /// @return  OK or FAIL
 int qf_process_qftf_option(void)
 {
-  return option_set_callback_func((char_u *)p_qftf, &qftf_cb);
+  return option_set_callback_func(p_qftf, &qftf_cb);
 }
 
 /// Update the w:quickfix_title variable in the quickfix/location list window in
@@ -4317,7 +4317,7 @@ static char *get_mef_name(void)
   static int off = 0;
 
   if (*p_mef == NUL) {
-    name = (char *)vim_tempname();
+    name = vim_tempname();
     if (name == NULL) {
       emsg(_(e_notmp));
     }
@@ -5153,7 +5153,7 @@ static bool vgr_match_buflines(qf_list_T *qfl, char *fname, buf_T *buf, char *sp
                          fname,
                          NULL,
                          duplicate_name ? 0 : buf->b_fnum,
-                         (char *)ml_get_buf(buf, regmatch->startpos[0].lnum + lnum, false),
+                         ml_get_buf(buf, regmatch->startpos[0].lnum + lnum, false),
                          regmatch->startpos[0].lnum + lnum,
                          regmatch->endpos[0].lnum + lnum,
                          regmatch->startpos[0].col + 1,
@@ -5180,7 +5180,7 @@ static bool vgr_match_buflines(qf_list_T *qfl, char *fname, buf_T *buf, char *sp
         }
       }
     } else {
-      char *const str = (char *)ml_get_buf(buf, lnum, false);
+      char *const str = ml_get_buf(buf, lnum, false);
       int score;
       uint32_t matches[MAX_FUZZY_MATCHES];
       const size_t sz = sizeof(matches) / sizeof(matches[0]);
@@ -5260,7 +5260,7 @@ static bool existing_swapfile(const buf_T *buf)
   FUNC_ATTR_NONNULL_ALL FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT
 {
   if (buf->b_ml.ml_mfp != NULL && buf->b_ml.ml_mfp->mf_fname != NULL) {
-    const char *const fname = (char *)buf->b_ml.ml_mfp->mf_fname;
+    const char *const fname = buf->b_ml.ml_mfp->mf_fname;
     const size_t len = STRLEN(fname);
 
     return fname[len - 1] != 'p' || fname[len - 2] != 'w';
diff --git a/src/nvim/regexp.c b/src/nvim/regexp.c
index ffa68c56b2..a94f91d103 100644
--- a/src/nvim/regexp.c
+++ b/src/nvim/regexp.c
@@ -137,7 +137,7 @@ static int re_multi_type(int c)
   return NOT_MULTI;
 }
 
-static char_u *reg_prev_sub = NULL;
+static char *reg_prev_sub = NULL;
 
 /*
  * REGEXP_INRANGE contains all characters which are always special in a []
@@ -1040,7 +1040,7 @@ static char_u *reg_getline(linenr_T lnum)
     // Must have matched the "\n" in the last line.
     return (char_u *)"";
   }
-  return ml_get_buf(rex.reg_buf, rex.reg_firstlnum + lnum, false);
+  return (char_u *)ml_get_buf(rex.reg_buf, rex.reg_firstlnum + lnum, false);
 }
 
 static char_u *reg_startzp[NSUBEXP];  // Workspace to mark beginning
@@ -1523,23 +1523,21 @@ static fptr_T do_Lower(int *d, int c)
   return (fptr_T)do_Lower;
 }
 
-/*
- * regtilde(): Replace tildes in the pattern by the old pattern.
- *
- * Short explanation of the tilde: It stands for the previous replacement
- * pattern.  If that previous pattern also contains a ~ we should go back a
- * step further...  But we insert the previous pattern into the current one
- * and remember that.
- * This still does not handle the case where "magic" changes.  So require the
- * user to keep his hands off of "magic".
- *
- * The tildes are parsed once before the first call to vim_regsub().
- */
-char_u *regtilde(char_u *source, int magic, bool preview)
+/// regtilde(): Replace tildes in the pattern by the old pattern.
+///
+/// Short explanation of the tilde: It stands for the previous replacement
+/// pattern.  If that previous pattern also contains a ~ we should go back a
+/// step further...  But we insert the previous pattern into the current one
+/// and remember that.
+/// This still does not handle the case where "magic" changes.  So require the
+/// user to keep his hands off of "magic".
+///
+/// The tildes are parsed once before the first call to vim_regsub().
+char *regtilde(char *source, int magic, bool preview)
 {
-  char_u *newsub = source;
-  char_u *tmpsub;
-  char_u *p;
+  char *newsub = source;
+  char *tmpsub;
+  char *p;
   int len;
   int prevlen;
 
@@ -1575,7 +1573,7 @@ char_u *regtilde(char_u *source, int magic, bool preview)
       if (*p == '\\' && p[1]) {         // skip escaped characters
         p++;
       }
-      p += utfc_ptr2len((char *)p) - 1;
+      p += utfc_ptr2len(p) - 1;
     }
   }
 
@@ -1584,7 +1582,7 @@ char_u *regtilde(char_u *source, int magic, bool preview)
     // Store a copy of newsub  in reg_prev_sub.  It is always allocated,
     // because recursive calls may make the returned string invalid.
     xfree(reg_prev_sub);
-    reg_prev_sub = vim_strsave(newsub);
+    reg_prev_sub = xstrdup(newsub);
   }
 
   return newsub;
@@ -1717,7 +1715,7 @@ int vim_regsub_multi(regmmatch_T *rmp, linenr_T lnum, char_u *source, char_u *de
 
 // When nesting more than a couple levels it's probably a mistake.
 #define MAX_REGSUB_NESTING 4
-static char_u *eval_result[MAX_REGSUB_NESTING] = { NULL, NULL, NULL, NULL };
+static char *eval_result[MAX_REGSUB_NESTING] = { NULL, NULL, NULL, NULL };
 
 #if defined(EXITFREE)
 void free_resub_eval_result(void)
@@ -1826,21 +1824,21 @@ static int vim_regsub_both(char_u *source, typval_T *expr, char_u *dest, int des
           eval_result[nested] = NULL;
         } else {
           char buf[NUMBUFLEN];
-          eval_result[nested] = (char_u *)tv_get_string_buf_chk(&rettv, buf);
+          eval_result[nested] = (char *)tv_get_string_buf_chk(&rettv, buf);
           if (eval_result[nested] != NULL) {
-            eval_result[nested] = vim_strsave(eval_result[nested]);
+            eval_result[nested] = xstrdup(eval_result[nested]);
           }
         }
         tv_clear(&rettv);
       } else {
-        eval_result[nested] = (char_u *)eval_to_string((char *)source + 2, NULL, true);
+        eval_result[nested] = eval_to_string((char *)source + 2, NULL, true);
       }
       nesting--;
 
       if (eval_result[nested] != NULL) {
         int had_backslash = false;
 
-        for (s = eval_result[nested]; *s != NUL; MB_PTR_ADV(s)) {
+        for (s = (char_u *)eval_result[nested]; *s != NUL; MB_PTR_ADV(s)) {
           // Change NL to CR, so that it becomes a line break,
           // unless called from vim_regexec_nl().
           // Skip over a backslashed character.
@@ -1862,9 +1860,9 @@ static int vim_regsub_both(char_u *source, typval_T *expr, char_u *dest, int des
         }
         if (had_backslash && (flags & REGSUB_BACKSLASH)) {
           // Backslashes will be consumed, need to double them.
-          s = vim_strsave_escaped(eval_result[nested], (char_u *)"\\");
+          s = vim_strsave_escaped((char_u *)eval_result[nested], (char_u *)"\\");
           xfree(eval_result[nested]);
-          eval_result[nested] = s;
+          eval_result[nested] = (char *)s;
         }
 
         dst += STRLEN(eval_result[nested]);
@@ -2466,12 +2464,12 @@ static bool vim_regexec_string(regmatch_T *rmp, char_u *line, colnr_T col, bool
       && result == NFA_TOO_EXPENSIVE) {
     int save_p_re = (int)p_re;
     int re_flags = (int)rmp->regprog->re_flags;
-    char_u *pat = vim_strsave(((nfa_regprog_T *)rmp->regprog)->pattern);
+    char *pat = xstrdup(((nfa_regprog_T *)rmp->regprog)->pattern);
 
     p_re = BACKTRACKING_ENGINE;
     vim_regfree(rmp->regprog);
-    report_re_switch(pat);
-    rmp->regprog = vim_regcomp((char *)pat, re_flags);
+    report_re_switch((char_u *)pat);
+    rmp->regprog = vim_regcomp(pat, re_flags);
     if (rmp->regprog != NULL) {
       rmp->regprog->re_in_use = true;
       result = rmp->regprog->engine->regexec_nl(rmp, line, col, nl);
@@ -2557,16 +2555,16 @@ long vim_regexec_multi(regmmatch_T *rmp, win_T *win, buf_T *buf, linenr_T lnum,
       && result == NFA_TOO_EXPENSIVE) {
     int save_p_re = (int)p_re;
     int re_flags = (int)rmp->regprog->re_flags;
-    char_u *pat = vim_strsave(((nfa_regprog_T *)rmp->regprog)->pattern);
+    char *pat = xstrdup(((nfa_regprog_T *)rmp->regprog)->pattern);
 
     p_re = BACKTRACKING_ENGINE;
     regprog_T *prev_prog = rmp->regprog;
 
-    report_re_switch(pat);
+    report_re_switch((char_u *)pat);
     // checking for \z misuse was already done when compiling for NFA,
     // allow all here
     reg_do_extmatch = REX_ALL;
-    rmp->regprog = vim_regcomp((char *)pat, re_flags);
+    rmp->regprog = vim_regcomp(pat, re_flags);
     reg_do_extmatch = 0;
 
     if (rmp->regprog == NULL) {
diff --git a/src/nvim/regexp_bt.c b/src/nvim/regexp_bt.c
index ccf2b60da2..63e4dd5b7e 100644
--- a/src/nvim/regexp_bt.c
+++ b/src/nvim/regexp_bt.c
@@ -1857,14 +1857,14 @@ static char_u *regatom(int *flagp)
       char_u *lp;
 
       ret = regnode(EXACTLY);
-      lp = reg_prev_sub;
+      lp = (char_u *)reg_prev_sub;
       while (*lp != NUL) {
         regc(*lp++);
       }
       regc(NUL);
       if (*reg_prev_sub != NUL) {
         *flagp |= HASWIDTH;
-        if ((lp - reg_prev_sub) == 1) {
+        if ((lp - (char_u *)reg_prev_sub) == 1) {
           *flagp |= SIMPLE;
         }
       }
diff --git a/src/nvim/regexp_defs.h b/src/nvim/regexp_defs.h
index b313dfe877..5d7175b89a 100644
--- a/src/nvim/regexp_defs.h
+++ b/src/nvim/regexp_defs.h
@@ -127,7 +127,7 @@ typedef struct {
   int has_zend;                         // pattern contains \ze
   int has_backref;                      // pattern contains \1 .. \9
   int reghasz;
-  char_u *pattern;
+  char *pattern;
   int nsubexp;                          // number of ()
   int nstate;
   nfa_state_T state[1];                 // actually longer..
diff --git a/src/nvim/regexp_nfa.c b/src/nvim/regexp_nfa.c
index 4c1058ba36..ea11398c30 100644
--- a/src/nvim/regexp_nfa.c
+++ b/src/nvim/regexp_nfa.c
@@ -1959,9 +1959,9 @@ static int nfa_regatom(void)
       emsg(_(e_nopresub));
       return FAIL;
     }
-    for (lp = reg_prev_sub; *lp != NUL; MB_CPTR_ADV(lp)) {
+    for (lp = (char_u *)reg_prev_sub; *lp != NUL; MB_CPTR_ADV(lp)) {
       EMIT(utf_ptr2char((char *)lp));
-      if (lp != reg_prev_sub) {
+      if (lp != (char_u *)reg_prev_sub) {
         EMIT(NFA_CONCAT);
       }
     }
@@ -7593,7 +7593,7 @@ static regprog_T *nfa_regcomp(char_u *expr, int re_flags)
 #endif
   // Remember whether this pattern has any \z specials in it.
   prog->reghasz = re_has_z;
-  prog->pattern = vim_strsave(expr);
+  prog->pattern = xstrdup((char *)expr);
 #ifdef REGEXP_DEBUG
   nfa_regengine.expr = NULL;
 #endif
diff --git a/src/nvim/screen.c b/src/nvim/screen.c
index d268dde845..8e10f2d62d 100644
--- a/src/nvim/screen.c
+++ b/src/nvim/screen.c
@@ -620,7 +620,7 @@ void setcursor_mayforce(bool force)
       // With 'rightleft' set and the cursor on a double-wide character,
       // position it on the leftmost column.
       col = curwin->w_width_inner - curwin->w_wcol
-            - ((utf_ptr2cells((char *)get_cursor_pos_ptr()) == 2
+            - ((utf_ptr2cells(get_cursor_pos_ptr()) == 2
                 && vim_isprintc(gchar_cursor())) ? 2 : 1);
     }
 
diff --git a/src/nvim/search.c b/src/nvim/search.c
index 490e79ebb0..e2df31c04f 100644
--- a/src/nvim/search.c
+++ b/src/nvim/search.c
@@ -175,11 +175,11 @@ int search_regcomp(char_u *pat, int pat_save, int pat_use, int options, regmmatc
   if (!(options & SEARCH_KEEP) && (cmdmod.cmod_flags & CMOD_KEEPPATTERNS) == 0) {
     // search or global command
     if (pat_save == RE_SEARCH || pat_save == RE_BOTH) {
-      save_re_pat(RE_SEARCH, pat, magic);
+      save_re_pat(RE_SEARCH, (char *)pat, magic);
     }
     // substitute or global command
     if (pat_save == RE_SUBST || pat_save == RE_BOTH) {
-      save_re_pat(RE_SUBST, pat, magic);
+      save_re_pat(RE_SUBST, (char *)pat, magic);
     }
   }
 
@@ -198,11 +198,11 @@ char_u *get_search_pat(void)
   return mr_pattern;
 }
 
-void save_re_pat(int idx, char_u *pat, int magic)
+void save_re_pat(int idx, char *pat, int magic)
 {
-  if (spats[idx].pat != pat) {
+  if (spats[idx].pat != (char_u *)pat) {
     free_spat(&spats[idx]);
-    spats[idx].pat = vim_strsave(pat);
+    spats[idx].pat = (char_u *)xstrdup(pat);
     spats[idx].magic = magic;
     spats[idx].no_scs = no_smartcase;
     spats[idx].timestamp = os_time();
@@ -225,11 +225,11 @@ void save_search_patterns(void)
   if (save_level++ == 0) {
     saved_spats[0] = spats[0];
     if (spats[0].pat != NULL) {
-      saved_spats[0].pat = vim_strsave(spats[0].pat);
+      saved_spats[0].pat = (char_u *)xstrdup((char *)spats[0].pat);
     }
     saved_spats[1] = spats[1];
     if (spats[1].pat != NULL) {
-      saved_spats[1].pat = vim_strsave(spats[1].pat);
+      saved_spats[1].pat = (char_u *)xstrdup((char *)spats[1].pat);
     }
     saved_spats_last_idx = last_idx;
     saved_spats_no_hlsearch = no_hlsearch;
@@ -296,7 +296,7 @@ void save_last_search_pattern(void)
 
   saved_last_search_spat = spats[RE_SEARCH];
   if (spats[RE_SEARCH].pat != NULL) {
-    saved_last_search_spat.pat = vim_strsave(spats[RE_SEARCH].pat);
+    saved_last_search_spat.pat = (char_u *)xstrdup((char *)spats[RE_SEARCH].pat);
   }
   saved_last_idx = last_idx;
   saved_no_hlsearch = no_hlsearch;
@@ -474,7 +474,7 @@ void set_last_search_pat(const char_u *s, int idx, int magic, int setlast)
     if (spats[idx].pat == NULL) {
       saved_spats[idx].pat = NULL;
     } else {
-      saved_spats[idx].pat = vim_strsave(spats[idx].pat);
+      saved_spats[idx].pat = (char_u *)xstrdup((char *)spats[idx].pat);
     }
     saved_spats_last_idx = last_idx;
   }
@@ -571,7 +571,7 @@ int searchit(win_T *win, buf_T *buf, pos_T *pos, pos_T *end_pos, Direction dir,
                && pos->lnum <= buf->b_ml.ml_line_count
                && pos->col < MAXCOL - 2) {
       // Watch out for the "col" being MAXCOL - 2, used in a closed fold.
-      ptr = ml_get_buf(buf, pos->lnum, false);
+      ptr = (char_u *)ml_get_buf(buf, pos->lnum, false);
       if ((int)STRLEN(ptr) <= pos->col) {
         start_char_len = 1;
       } else {
@@ -642,7 +642,7 @@ int searchit(win_T *win, buf_T *buf, pos_T *pos, pos_T *end_pos, Direction dir,
           if (lnum + matchpos.lnum > buf->b_ml.ml_line_count) {
             ptr = (char_u *)"";
           } else {
-            ptr = ml_get_buf(buf, lnum + matchpos.lnum, false);
+            ptr = (char_u *)ml_get_buf(buf, lnum + matchpos.lnum, false);
           }
 
           // Forward search in the first line: match should be after
@@ -711,7 +711,7 @@ int searchit(win_T *win, buf_T *buf, pos_T *pos, pos_T *end_pos, Direction dir,
               }
               // Need to get the line pointer again, a multi-line search may
               // have made it invalid.
-              ptr = ml_get_buf(buf, lnum, false);
+              ptr = (char_u *)ml_get_buf(buf, lnum, false);
             }
             if (!match_ok) {
               continue;
@@ -794,7 +794,7 @@ int searchit(win_T *win, buf_T *buf, pos_T *pos, pos_T *end_pos, Direction dir,
               }
               // Need to get the line pointer again, a
               // multi-line search may have made it invalid.
-              ptr = ml_get_buf(buf, lnum + matchpos.lnum, false);
+              ptr = (char_u *)ml_get_buf(buf, lnum + matchpos.lnum, false);
             }
 
             // If there is only a match after the cursor, skip
@@ -822,7 +822,7 @@ int searchit(win_T *win, buf_T *buf, pos_T *pos, pos_T *end_pos, Direction dir,
             } else {
               pos->col--;
               if (pos->lnum <= buf->b_ml.ml_line_count) {
-                ptr = ml_get_buf(buf, pos->lnum, false);
+                ptr = (char_u *)ml_get_buf(buf, pos->lnum, false);
                 pos->col -= utf_head_off((char *)ptr, (char *)ptr + pos->col);
               }
             }
@@ -1443,7 +1443,7 @@ int search_for_exact_line(buf_T *buf, pos_T *pos, Direction dir, char_u *pat)
     if (start == 0) {
       start = pos->lnum;
     }
-    ptr = ml_get_buf(buf, pos->lnum, false);
+    ptr = (char_u *)ml_get_buf(buf, pos->lnum, false);
     p = (char_u *)skipwhite((char *)ptr);
     pos->col = (colnr_T)(p - ptr);
 
@@ -2717,7 +2717,7 @@ static void update_search_stat(int dirc, pos_T *pos, pos_T *cursor_pos, searchst
     }
     if (done_search) {
       xfree(lastpat);
-      lastpat = vim_strsave(spats[last_idx].pat);
+      lastpat = (char_u *)xstrdup((char *)spats[last_idx].pat);
       chgtick = (int)buf_get_changedtick(curbuf);
       lbuf = curbuf;
       lastpos = p;
@@ -2827,7 +2827,7 @@ void f_searchcount(typval_T *argvars, typval_T *rettv, EvalFuncData fptr)
       goto the_end;
     }
     xfree(spats[last_idx].pat);
-    spats[last_idx].pat = vim_strsave(pattern);
+    spats[last_idx].pat = (char_u *)xstrdup((char *)pattern);
   }
   if (spats[last_idx].pat == NULL || *spats[last_idx].pat == NUL) {
     goto the_end;  // the previous pattern was never defined
@@ -3103,7 +3103,7 @@ bool fuzzy_match(char_u *const str, const char_u *const pat_arg, const bool matc
 
   *outScore = 0;
 
-  char_u *const save_pat = vim_strsave(pat_arg);
+  char_u *const save_pat = (char_u *)xstrdup((char *)pat_arg);
   char_u *pat = save_pat;
   char_u *p = pat;
 
diff --git a/src/nvim/shada.c b/src/nvim/shada.c
index 1a70b77053..312c30e4a9 100644
--- a/src/nvim/shada.c
+++ b/src/nvim/shada.c
@@ -1238,7 +1238,7 @@ static void shada_read(ShaDaReadDef *const sd_reader, const int flags)
       // string is close to useless: you can only use it with :& or :~ and
       // that’s all because s//~ is not available until the first call to
       // regtilde. Vim was not calling this for some reason.
-      (void)(char *)regtilde((char_u *)cur_entry.data.sub_string.sub, p_magic, false);
+      (void)regtilde(cur_entry.data.sub_string.sub, p_magic, false);
       // Do not free shada entry: its allocated memory was saved above.
       break;
     case kSDItemHistoryEntry:
diff --git a/src/nvim/spell.c b/src/nvim/spell.c
index 30e256b37a..7f07d2ff2c 100644
--- a/src/nvim/spell.c
+++ b/src/nvim/spell.c
@@ -194,8 +194,8 @@ int did_set_spelltab;
 char *e_format = N_("E759: Format error in spell file");
 
 // Remember what "z?" replaced.
-char_u *repl_from = NULL;
-char_u *repl_to = NULL;
+char *repl_from = NULL;
+char *repl_to = NULL;
 
 /// Main spell-checking function.
 /// "ptr" points to a character that could be the start of a word.
@@ -1275,7 +1275,7 @@ size_t spell_move_to(win_T *wp, int dir, bool allwords, bool curline, hlf_T *att
   decor_spell_nav_start(wp);
 
   while (!got_int) {
-    char_u *line = ml_get_buf(wp->w_buffer, lnum, false);
+    char_u *line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
 
     len = STRLEN(line);
     if (buflen < len + MAXWLEN + 2) {
@@ -1302,7 +1302,7 @@ size_t spell_move_to(win_T *wp, int dir, bool allwords, bool curline, hlf_T *att
 
       // Need to get the line again, may have looked at the previous
       // one.
-      line = ml_get_buf(wp->w_buffer, lnum, false);
+      line = (char_u *)ml_get_buf(wp->w_buffer, lnum, false);
     }
 
     // Copy the line into "buf" and append the start of the next line if
@@ -1312,7 +1312,7 @@ size_t spell_move_to(win_T *wp, int dir, bool allwords, bool curline, hlf_T *att
     STRCPY(buf, line);
     if (lnum < wp->w_buffer->b_ml.ml_line_count) {
       spell_cat_line(buf + STRLEN(buf),
-                     ml_get_buf(wp->w_buffer, lnum + 1, false),
+                     (char_u *)ml_get_buf(wp->w_buffer, lnum + 1, false),
                      MAXWLEN);
     }
     char_u *p = buf + skip;
@@ -1573,15 +1573,15 @@ static void int_wordlist_spl(char_u *fname)
                int_wordlist, spell_enc());
 }
 
-// Allocate a new slang_T for language "lang".  "lang" can be NULL.
-// Caller must fill "sl_next".
-slang_T *slang_alloc(char_u *lang)
+/// Allocate a new slang_T for language "lang".  "lang" can be NULL.
+/// Caller must fill "sl_next".
+slang_T *slang_alloc(char *lang)
   FUNC_ATTR_NONNULL_RET
 {
   slang_T *lp = xcalloc(1, sizeof(slang_T));
 
   if (lang != NULL) {
-    lp->sl_name = vim_strsave(lang);
+    lp->sl_name = xstrdup(lang);
   }
   ga_init(&lp->sl_rep, sizeof(fromto_T), 10);
   ga_init(&lp->sl_repsal, sizeof(fromto_T), 10);
@@ -1693,7 +1693,7 @@ void slang_clear_sug(slang_T *lp)
 static void spell_load_cb(char *fname, void *cookie)
 {
   spelload_T *slp = (spelload_T *)cookie;
-  slang_T *slang = spell_load_file((char_u *)fname, slp->sl_lang, NULL, false);
+  slang_T *slang = spell_load_file(fname, (char *)slp->sl_lang, NULL, false);
   if (slang != NULL) {
     // When a previously loaded file has NOBREAK also use it for the
     // ".add" files.
@@ -1861,7 +1861,7 @@ char *did_set_spelllang(win_T *wp)
   langp_T *lp, *lp2;
   static bool recursive = false;
   char *ret_msg = NULL;
-  char_u *spl_copy;
+  char *spl_copy;
 
   bufref_T bufref;
   set_bufref(&bufref, wp->w_buffer);
@@ -1879,12 +1879,12 @@ char *did_set_spelllang(win_T *wp)
 
   // Make a copy of 'spelllang', the SpellFileMissing autocommands may change
   // it under our fingers.
-  spl_copy = vim_strsave((char_u *)wp->w_s->b_p_spl);
+  spl_copy = xstrdup(wp->w_s->b_p_spl);
 
   wp->w_s->b_cjk = 0;
 
   // Loop over comma separated language names.
-  for (splp = (char *)spl_copy; *splp != NUL;) {
+  for (splp = spl_copy; *splp != NUL;) {
     // Get one language name.
     copy_option_part(&splp, (char *)lang, MAXWLEN, ",");
     region = NULL;
@@ -1952,7 +1952,7 @@ char *did_set_spelllang(win_T *wp)
     // If not found try loading the language now.
     if (slang == NULL) {
       if (filename) {
-        (void)spell_load_file(lang, lang, NULL, false);
+        (void)spell_load_file((char *)lang, (char *)lang, NULL, false);
       } else {
         spell_load_lang(lang);
         // SpellFileMissing autocommands may do anything, including
@@ -2054,7 +2054,7 @@ char *did_set_spelllang(win_T *wp)
           *p = NUL;             // truncate at ".encoding.add"
         }
       }
-      slang = spell_load_file(spf_name, lang, NULL, true);
+      slang = spell_load_file((char *)spf_name, (char *)lang, NULL, true);
 
       // If one of the languages has NOBREAK we assume the addition
       // files also have this.
diff --git a/src/nvim/spell_defs.h b/src/nvim/spell_defs.h
index 27b9777dc2..2c4aebe420 100644
--- a/src/nvim/spell_defs.h
+++ b/src/nvim/spell_defs.h
@@ -115,7 +115,7 @@ typedef struct slang_S slang_T;
 
 struct slang_S {
   slang_T *sl_next;         // next language
-  char_u *sl_name;          // language name "en", "en.rare", "nl", etc.
+  char *sl_name;            // language name "en", "en.rare", "nl", etc.
   char *sl_fname;           // name of .spl file
   bool sl_add;              // true if it's a .add file.
 
@@ -252,7 +252,7 @@ typedef struct wordcount_S {
 #define MAXWORDCOUNT 0xffff
 
 // Remember what "z?" replaced.
-extern char_u *repl_from;
-extern char_u *repl_to;
+extern char *repl_from;
+extern char *repl_to;
 
 #endif  // NVIM_SPELL_DEFS_H
diff --git a/src/nvim/spellfile.c b/src/nvim/spellfile.c
index 661ca54fad..e6e56d615c 100644
--- a/src/nvim/spellfile.c
+++ b/src/nvim/spellfile.c
@@ -572,10 +572,10 @@ static inline int spell_check_magic_string(FILE *const fd)
 /// @param silent  no error if file doesn't exist
 ///
 /// @return  the slang_T the spell file was loaded into.  NULL for error.
-slang_T *spell_load_file(char_u *fname, char_u *lang, slang_T *old_lp, bool silent)
+slang_T *spell_load_file(char *fname, char *lang, slang_T *old_lp, bool silent)
 {
   FILE *fd;
-  char_u *p;
+  char *p;
   int n;
   int len;
   slang_T *lp = NULL;
@@ -583,7 +583,7 @@ slang_T *spell_load_file(char_u *fname, char_u *lang, slang_T *old_lp, bool sile
   int res;
   bool did_estack_push = false;
 
-  fd = os_fopen((char *)fname, "r");
+  fd = os_fopen(fname, "r");
   if (fd == NULL) {
     if (!silent) {
       semsg(_(e_notopen), fname);
@@ -604,16 +604,16 @@ slang_T *spell_load_file(char_u *fname, char_u *lang, slang_T *old_lp, bool sile
     lp = slang_alloc(lang);
 
     // Remember the file name, used to reload the file when it's updated.
-    lp->sl_fname = (char *)vim_strsave(fname);
+    lp->sl_fname = xstrdup(fname);
 
     // Check for .add.spl.
-    lp->sl_add = strstr(path_tail((char *)fname), SPL_FNAME_ADD) != NULL;
+    lp->sl_add = strstr(path_tail(fname), SPL_FNAME_ADD) != NULL;
   } else {
     lp = old_lp;
   }
 
   // Set sourcing_name, so that error messages mention the file name.
-  estack_push(ETYPE_SPELL, (char *)fname, 0);
+  estack_push(ETYPE_SPELL, fname, 0);
   did_estack_push = true;
 
   // <HEADER>: <fileID>
@@ -697,11 +697,11 @@ slang_T *spell_load_file(char_u *fname, char_u *lang, slang_T *old_lp, bool sile
       break;
 
     case SN_MAP:
-      p = READ_STRING(fd, len);                         // <mapstr>
+      p = (char *)READ_STRING(fd, len);                         // <mapstr>
       if (p == NULL) {
         goto endFAIL;
       }
-      set_map_str(lp, p);
+      set_map_str(lp, (char_u *)p);
       xfree(p);
       break;
 
@@ -1824,7 +1824,7 @@ static void spell_reload_one(char_u *fname, bool added_word)
   for (slang = first_lang; slang != NULL; slang = slang->sl_next) {
     if (path_full_compare((char *)fname, slang->sl_fname, false, true) == kEqualFiles) {
       slang_clear(slang);
-      if (spell_load_file(fname, NULL, slang, false) == NULL) {
+      if (spell_load_file((char *)fname, NULL, slang, false) == NULL) {
         // reloading failed, clear the language
         slang_clear(slang);
       }
@@ -2005,17 +2005,17 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
   char_u *line;
   char_u *pc = NULL;
 #define MAXITEMCNT  30
-  char_u *(items[MAXITEMCNT]);
+  char *(items[MAXITEMCNT]);
   int itemcnt;
-  char_u *p;
+  char *p;
   int lnum = 0;
   affheader_T *cur_aff = NULL;
   bool did_postpone_prefix = false;
   int aff_todo = 0;
   hashtab_T *tp;
-  char_u *low = NULL;
-  char_u *fol = NULL;
-  char_u *upp = NULL;
+  char *low = NULL;
+  char *fol = NULL;
+  char *upp = NULL;
   int do_rep;
   int do_repsal;
   int do_sal;
@@ -2090,8 +2090,8 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
     // Split the line up in white separated items.  Put a NUL after each
     // item.
     itemcnt = 0;
-    for (p = line;;) {
-      while (*p != NUL && *p <= ' ') {  // skip white space and CR/NL
+    for (p = (char *)line;;) {
+      while (*p != NUL && (uint8_t)(*p) <= ' ') {  // skip white space and CR/NL
         p++;
       }
       if (*p == NUL) {
@@ -2102,12 +2102,12 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
       }
       items[itemcnt++] = p;
       // A few items have arbitrary text argument, don't split them.
-      if (itemcnt == 2 && spell_info_item(items[0])) {
-        while (*p >= ' ' || *p == TAB) {  // skip until CR/NL
+      if (itemcnt == 2 && spell_info_item((char_u *)items[0])) {
+        while ((uint8_t)(*p) >= ' ' || *p == TAB) {  // skip until CR/NL
           p++;
         }
       } else {
-        while (*p > ' ') {  // skip until white space or CR/NL
+        while ((uint8_t)(*p) > ' ') {  // skip until white space or CR/NL
           p++;
         }
       }
@@ -2154,7 +2154,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
           smsg(_("FLAG after using flags in %s line %d: %s"),
                fname, lnum, items[1]);
         }
-      } else if (spell_info_item(items[0]) && itemcnt > 1) {
+      } else if (spell_info_item((char_u *)items[0]) && itemcnt > 1) {
         p = getroom(spin,
                     (spin->si_info == NULL ? 0 : STRLEN(spin->si_info))
                     + STRLEN(items[0])
@@ -2166,9 +2166,9 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         STRCAT(p, items[0]);
         STRCAT(p, " ");
         STRCAT(p, items[1]);
-        spin->si_info = p;
+        spin->si_info = (char_u *)p;
       } else if (is_aff_rule(items, itemcnt, "MIDWORD", 2) && midword == NULL) {
-        midword = (char_u *)getroom_save(spin, items[1]);
+        midword = (char_u *)getroom_save(spin, (char_u *)items[1]);
       } else if (is_aff_rule(items, itemcnt, "TRY", 2)) {
         // ignored, we look in the tree for what chars may appear
       }
@@ -2176,44 +2176,44 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
       else if ((is_aff_rule(items, itemcnt, "RAR", 2)
                 || is_aff_rule(items, itemcnt, "RARE", 2))
                && aff->af_rare == 0) {
-        aff->af_rare = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_rare = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                     fname, lnum);
       }
       // TODO: remove "KEP" later
       else if ((is_aff_rule(items, itemcnt, "KEP", 2)
                 || is_aff_rule(items, itemcnt, "KEEPCASE", 2))
                && aff->af_keepcase == 0) {
-        aff->af_keepcase = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_keepcase = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                         fname, lnum);
       } else if ((is_aff_rule(items, itemcnt, "BAD", 2)
                   || is_aff_rule(items, itemcnt, "FORBIDDENWORD", 2))
                  && aff->af_bad == 0) {
-        aff->af_bad = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_bad = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                    fname, lnum);
       } else if (is_aff_rule(items, itemcnt, "NEEDAFFIX", 2)
                  && aff->af_needaffix == 0) {
-        aff->af_needaffix = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_needaffix = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                          fname, lnum);
       } else if (is_aff_rule(items, itemcnt, "CIRCUMFIX", 2)
                  && aff->af_circumfix == 0) {
-        aff->af_circumfix = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_circumfix = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                          fname, lnum);
       } else if (is_aff_rule(items, itemcnt, "NOSUGGEST", 2)
                  && aff->af_nosuggest == 0) {
-        aff->af_nosuggest = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_nosuggest = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                          fname, lnum);
       } else if ((is_aff_rule(items, itemcnt, "NEEDCOMPOUND", 2)
                   || is_aff_rule(items, itemcnt, "ONLYINCOMPOUND", 2))
                  && aff->af_needcomp == 0) {
-        aff->af_needcomp = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_needcomp = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                         fname, lnum);
       } else if (is_aff_rule(items, itemcnt, "COMPOUNDROOT", 2)
                  && aff->af_comproot == 0) {
-        aff->af_comproot = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_comproot = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                         fname, lnum);
       } else if (is_aff_rule(items, itemcnt, "COMPOUNDFORBIDFLAG", 2)
                  && aff->af_compforbid == 0) {
-        aff->af_compforbid = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_compforbid = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                           fname, lnum);
         if (aff->af_pref.ht_used > 0) {
           smsg(_("Defining COMPOUNDFORBIDFLAG after PFX item may give wrong results in %s line %d"),
@@ -2221,7 +2221,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         }
       } else if (is_aff_rule(items, itemcnt, "COMPOUNDPERMITFLAG", 2)
                  && aff->af_comppermit == 0) {
-        aff->af_comppermit = affitem2flag(aff->af_flagtype, items[1],
+        aff->af_comppermit = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                           fname, lnum);
         if (aff->af_pref.ht_used > 0) {
           smsg(_("Defining COMPOUNDPERMITFLAG after PFX item may give wrong results in %s line %d"),
@@ -2234,7 +2234,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         p = getroom(spin, STRLEN(items[1]) + 2, false);
         STRCPY(p, items[1]);
         STRCAT(p, "+");
-        compflags = p;
+        compflags = (char_u *)p;
       } else if (is_aff_rule(items, itemcnt, "COMPOUNDRULES", 2)) {
         // We don't use the count, but do check that it's a number and
         // not COMPOUNDRULE mistyped.
@@ -2257,7 +2257,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
             STRCAT(p, "/");
           }
           STRCAT(p, items[1]);
-          compflags = p;
+          compflags = (char_u *)p;
         }
       } else if (is_aff_rule(items, itemcnt, "COMPOUNDWORDMAX", 2)
                  && compmax == 0) {
@@ -2306,12 +2306,12 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         }
         if (i >= gap->ga_len) {
           ga_grow(gap, 2);
-          ((char **)(gap->ga_data))[gap->ga_len++] = getroom_save(spin, items[1]);
-          ((char **)(gap->ga_data))[gap->ga_len++] = getroom_save(spin, items[2]);
+          ((char **)(gap->ga_data))[gap->ga_len++] = getroom_save(spin, (char_u *)items[1]);
+          ((char **)(gap->ga_data))[gap->ga_len++] = getroom_save(spin, (char_u *)items[2]);
         }
       } else if (is_aff_rule(items, itemcnt, "SYLLABLE", 2)
                  && syllable == NULL) {
-        syllable = (char_u *)getroom_save(spin, items[1]);
+        syllable = (char_u *)getroom_save(spin, (char_u *)items[1]);
       } else if (is_aff_rule(items, itemcnt, "NOBREAK", 1)) {
         spin->si_nobreak = true;
       } else if (is_aff_rule(items, itemcnt, "NOSPLITSUGS", 1)) {
@@ -2356,7 +2356,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         } else {
           // New affix letter.
           cur_aff = getroom(spin, sizeof(*cur_aff), true);
-          cur_aff->ah_flag = affitem2flag(aff->af_flagtype, items[1],
+          cur_aff->ah_flag = affitem2flag(aff->af_flagtype, (char_u *)items[1],
                                           fname, lnum);
           if (cur_aff->ah_flag == 0 || STRLEN(items[1]) >= AH_KEY_LEN) {
             break;
@@ -2444,10 +2444,10 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
         aff_entry = getroom(spin, sizeof(*aff_entry), true);
 
         if (STRCMP(items[2], "0") != 0) {
-          aff_entry->ae_chop = (char_u *)getroom_save(spin, items[2]);
+          aff_entry->ae_chop = (char_u *)getroom_save(spin, (char_u *)items[2]);
         }
         if (STRCMP(items[3], "0") != 0) {
-          aff_entry->ae_add = (char_u *)getroom_save(spin, items[3]);
+          aff_entry->ae_add = (char_u *)getroom_save(spin, (char_u *)items[3]);
 
           // Recognize flags on the affix: abcd/XYZ
           aff_entry->ae_flags = (char_u *)vim_strchr((char *)aff_entry->ae_add, '/');
@@ -2467,7 +2467,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
           if (STRCMP(items[4], ".") != 0) {
             char_u buf[MAXLINELEN];
 
-            aff_entry->ae_cond = (char_u *)getroom_save(spin, items[4]);
+            aff_entry->ae_cond = (char_u *)getroom_save(spin, (char_u *)items[4]);
             if (*items[0] == 'P') {
               sprintf((char *)buf, "^%s", items[4]);
             } else {
@@ -2502,10 +2502,10 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
               if (c_up != c
                   && (aff_entry->ae_cond == NULL
                       || utf_ptr2char((char *)aff_entry->ae_cond) == c)) {
-                p = aff_entry->ae_add
+                p = (char *)aff_entry->ae_add
                     + STRLEN(aff_entry->ae_add);
                 MB_PTR_BACK(aff_entry->ae_add, p);
-                if (utf_ptr2char((char *)p) == c_up) {
+                if (utf_ptr2char(p) == c_up) {
                   upper = true;
                   aff_entry->ae_chop = NULL;
                   *p = NUL;
@@ -2515,7 +2515,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
                   // upper-case letter.
                   if (aff_entry->ae_cond != NULL) {
                     char_u buf[MAXLINELEN];
-                    onecap_copy(items[4], buf, true);
+                    onecap_copy((char_u *)items[4], buf, true);
                     aff_entry->ae_cond = (char_u *)getroom_save(spin, buf);
                     if (aff_entry->ae_cond != NULL) {
                       sprintf((char *)buf, "^%s",
@@ -2534,10 +2534,9 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
               int n;
 
               // Find a previously used condition.
-              for (idx = spin->si_prefcond.ga_len - 1; idx >= 0;
-                   --idx) {
-                p = ((char_u **)spin->si_prefcond.ga_data)[idx];
-                if (str_equal(p, aff_entry->ae_cond)) {
+              for (idx = spin->si_prefcond.ga_len - 1; idx >= 0; idx--) {
+                p = ((char **)spin->si_prefcond.ga_data)[idx];
+                if (str_equal((char_u *)p, aff_entry->ae_cond)) {
                   break;
                 }
               }
@@ -2551,9 +2550,9 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
 
               // Add the prefix to the prefix tree.
               if (aff_entry->ae_add == NULL) {
-                p = (char_u *)"";
+                p = "";
               } else {
-                p = aff_entry->ae_add;
+                p = (char *)aff_entry->ae_add;
               }
 
               // PFX_FLAGS is a negative number, so that
@@ -2571,7 +2570,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
               if (aff_entry->ae_compforbid) {
                 n |= WFP_COMPFORBID;
               }
-              tree_add_word(spin, p, spin->si_prefroot, n,
+              tree_add_word(spin, (char_u *)p, spin->si_prefroot, n,
                             idx, cur_aff->ah_newID);
               did_postpone_prefix = true;
             }
@@ -2584,11 +2583,11 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
           }
         }
       } else if (is_aff_rule(items, itemcnt, "FOL", 2) && fol == NULL) {
-        fol = vim_strsave(items[1]);
+        fol = xstrdup(items[1]);
       } else if (is_aff_rule(items, itemcnt, "LOW", 2) && low == NULL) {
-        low = vim_strsave(items[1]);
+        low = xstrdup(items[1]);
       } else if (is_aff_rule(items, itemcnt, "UPP", 2) && upp == NULL) {
-        upp = vim_strsave(items[1]);
+        upp = xstrdup(items[1]);
       } else if (is_aff_rule(items, itemcnt, "REP", 2)
                  || is_aff_rule(items, itemcnt, "REPSAL", 2)) {
         // Ignore REP/REPSAL count
@@ -2619,8 +2618,8 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
             }
           }
           add_fromto(spin, items[0][3] == 'S'
-              ? &spin->si_repsal
-              : &spin->si_rep, items[1], items[2]);
+                     ? &spin->si_repsal
+                     : &spin->si_rep, (char_u *)items[1], (char_u *)items[2]);
         }
       } else if (is_aff_rule(items, itemcnt, "MAP", 2)) {
         // MAP item or count
@@ -2640,7 +2639,7 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
             if ((!GA_EMPTY(&spin->si_map)
                  && vim_strchr(spin->si_map.ga_data, c)
                  != NULL)
-                || vim_strchr((char *)p, c) != NULL) {
+                || vim_strchr(p, c) != NULL) {
               smsg(_("Duplicate character in MAP in %s line %d"),
                    fname, lnum);
             }
@@ -2658,31 +2657,31 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
           // SAL item (sounds-a-like)
           // Either one of the known keys or a from-to pair.
           if (STRCMP(items[1], "followup") == 0) {
-            spin->si_followup = sal_to_bool(items[2]);
+            spin->si_followup = sal_to_bool((char_u *)items[2]);
           } else if (STRCMP(items[1], "collapse_result") == 0) {
-            spin->si_collapse = sal_to_bool(items[2]);
+            spin->si_collapse = sal_to_bool((char_u *)items[2]);
           } else if (STRCMP(items[1], "remove_accents") == 0) {
-            spin->si_rem_accents = sal_to_bool(items[2]);
+            spin->si_rem_accents = sal_to_bool((char_u *)items[2]);
           } else {
             // when "to" is "_" it means empty
-            add_fromto(spin, &spin->si_sal, items[1],
+            add_fromto(spin, &spin->si_sal, (char_u *)items[1],
                        STRCMP(items[2], "_") == 0 ? (char_u *)""
-                                                  : items[2]);
+                       : (char_u *)items[2]);
           }
         }
       } else if (is_aff_rule(items, itemcnt, "SOFOFROM", 2)
                  && sofofrom == NULL) {
-        sofofrom = (char_u *)getroom_save(spin, items[1]);
+        sofofrom = (char_u *)getroom_save(spin, (char_u *)items[1]);
       } else if (is_aff_rule(items, itemcnt, "SOFOTO", 2)
                  && sofoto == NULL) {
-        sofoto = (char_u *)getroom_save(spin, items[1]);
+        sofoto = (char_u *)getroom_save(spin, (char_u *)items[1]);
       } else if (STRCMP(items[0], "COMMON") == 0) {
         int i;
 
         for (i = 1; i < itemcnt; i++) {
           if (HASHITEM_EMPTY(hash_find(&spin->si_commonwords, (char *)items[i]))) {
-            p = vim_strsave(items[i]);
-            hash_add(&spin->si_commonwords, p);
+            p = xstrdup(items[i]);
+            hash_add(&spin->si_commonwords, (char_u *)p);
           }
         }
       } else {
@@ -2773,9 +2772,9 @@ static afffile_T *spell_read_aff(spellinfo_T *spin, char_u *fname)
   return aff;
 }
 
-// Returns true when items[0] equals "rulename", there are "mincount" items or
-// a comment is following after item "mincount".
-static bool is_aff_rule(char_u **items, int itemcnt, char *rulename, int mincount)
+/// @return  true when items[0] equals "rulename", there are "mincount" items or
+///          a comment is following after item "mincount".
+static bool is_aff_rule(char **items, int itemcnt, char *rulename, int mincount)
 {
   return STRCMP(items[0], rulename) == 0
          && (itemcnt == mincount
@@ -4914,7 +4913,7 @@ static void spell_make_sugfile(spellinfo_T *spin, char *wfname)
   }
   if (slang == NULL) {
     spell_message(spin, _("Reading back spell file..."));
-    slang = spell_load_file((char_u *)wfname, NULL, NULL, false);
+    slang = spell_load_file(wfname, NULL, NULL, false);
     if (slang == NULL) {
       return;
     }
@@ -5233,7 +5232,7 @@ static void sug_write(spellinfo_T *spin, char_u *fname)
 
   for (linenr_T lnum = 1; lnum <= wcount; lnum++) {
     // <sugline>: <sugnr> ... NUL
-    char_u *line = ml_get_buf(spin->si_spellbuf, lnum, false);
+    char_u *line = (char_u *)ml_get_buf(spin->si_spellbuf, lnum, false);
     size_t len = STRLEN(line) + 1;
     if (fwrite(line, len, 1, fd) == 0) {
       emsg(_(e_write));
@@ -5531,7 +5530,7 @@ void spell_add_word(char_u *word, int len, SpellAddType what, int idx, bool undo
 
   if (idx == 0) {           // use internal wordlist
     if (int_wordlist == NULL) {
-      int_wordlist = vim_tempname();
+      int_wordlist = (char_u *)vim_tempname();
       if (int_wordlist == NULL) {
         return;
       }
diff --git a/src/nvim/spellsuggest.c b/src/nvim/spellsuggest.c
index c07e460ea8..c38fa2b24f 100644
--- a/src/nvim/spellsuggest.c
+++ b/src/nvim/spellsuggest.c
@@ -407,7 +407,7 @@ int spell_check_sps(void)
 /// When "count" is non-zero use that suggestion.
 void spell_suggest(int count)
 {
-  char_u *line;
+  char *line;
   pos_T prev_cursor = curwin->w_cursor;
   char_u wcopy[MAXWLEN + 2];
   char_u *p;
@@ -453,10 +453,10 @@ void spell_suggest(int count)
     // No bad word or it starts after the cursor: use the word under the
     // cursor.
     curwin->w_cursor = prev_cursor;
-    line = (char_u *)get_cursor_line_ptr();
-    p = line + curwin->w_cursor.col;
+    line = get_cursor_line_ptr();
+    p = (char_u *)line + curwin->w_cursor.col;
     // Backup to before start of word.
-    while (p > line && spell_iswordp_nmw(p, curwin)) {
+    while (p > (char_u *)line && spell_iswordp_nmw(p, curwin)) {
       MB_PTR_BACK(line, p);
     }
     // Forward to start of word.
@@ -468,7 +468,7 @@ void spell_suggest(int count)
       beep_flush();
       return;
     }
-    curwin->w_cursor.col = (colnr_T)(p - line);
+    curwin->w_cursor.col = (colnr_T)(p - (char_u *)line);
   }
 
   // Get the word and its length.
@@ -477,7 +477,7 @@ void spell_suggest(int count)
   need_cap = check_need_cap(curwin->w_cursor.lnum, curwin->w_cursor.col);
 
   // Make a copy of current line since autocommands may free the line.
-  line = vim_strsave((char_u *)get_cursor_line_ptr());
+  line = xstrdup(get_cursor_line_ptr());
   spell_suggest_timeout = 5000;
 
   // Get the list of suggestions.  Limit to 'lines' - 2 or the number in
@@ -487,7 +487,7 @@ void spell_suggest(int count)
   } else {
     limit = sps_limit;
   }
-  spell_find_suggest(line + curwin->w_cursor.col, badlen, &sug, limit,
+  spell_find_suggest((char_u *)line + curwin->w_cursor.col, badlen, &sug, limit,
                      true, need_cap, true);
 
   if (GA_EMPTY(&sug.su_ga)) {
@@ -593,20 +593,20 @@ void spell_suggest(int count)
     if (sug.su_badlen > stp->st_orglen) {
       // Replacing less than "su_badlen", append the remainder to
       // repl_to.
-      repl_from = (char_u *)xstrnsave((char *)sug.su_badptr, (size_t)sug.su_badlen);
+      repl_from = xstrnsave((char *)sug.su_badptr, (size_t)sug.su_badlen);
       vim_snprintf((char *)IObuff, IOSIZE, "%s%.*s", stp->st_word,
                    sug.su_badlen - stp->st_orglen,
                    sug.su_badptr + stp->st_orglen);
-      repl_to = vim_strsave(IObuff);
+      repl_to = xstrdup((char *)IObuff);
     } else {
       // Replacing su_badlen or more, use the whole word.
-      repl_from = (char_u *)xstrnsave((char *)sug.su_badptr, (size_t)stp->st_orglen);
-      repl_to = vim_strsave((char_u *)stp->st_word);
+      repl_from = xstrnsave((char *)sug.su_badptr, (size_t)stp->st_orglen);
+      repl_to = xstrdup(stp->st_word);
     }
 
     // Replace the word.
     p = xmalloc(STRLEN(line) - (size_t)stp->st_orglen + (size_t)stp->st_wordlen + 1);
-    c = (int)(sug.su_badptr - line);
+    c = (int)(sug.su_badptr - (char_u *)line);
     memmove(p, line, (size_t)c);
     STRCPY(p + c, stp->st_word);
     STRCAT(p, sug.su_badptr + stp->st_orglen);
@@ -678,7 +678,7 @@ static void spell_find_suggest(char_u *badptr, int badlen, suginfo_T *su, int ma
   char_u buf[MAXPATHL];
   char *p;
   bool do_combine = false;
-  char_u *sps_copy;
+  char *sps_copy;
   static bool expr_busy = false;
   int c;
   langp_T *lp;
@@ -758,10 +758,10 @@ static void spell_find_suggest(char_u *badptr, int badlen, suginfo_T *su, int ma
   }
 
   // Make a copy of 'spellsuggest', because the expression may change it.
-  sps_copy = vim_strsave((char_u *)p_sps);
+  sps_copy = xstrdup(p_sps);
 
   // Loop over the items in 'spellsuggest'.
-  for (p = (char *)sps_copy; *p != NUL;) {
+  for (p = sps_copy; *p != NUL;) {
     copy_option_part(&p, (char *)buf, MAXPATHL, ",");
 
     if (STRNCMP(buf, "expr:", 5) == 0) {
@@ -2806,7 +2806,7 @@ static void add_sound_suggest(suginfo_T *su, char_u *goodword, int score, langp_
   }
 
   // Go over the list of good words that produce this soundfold word
-  nrline = ml_get_buf(slang->sl_sugbuf, (linenr_T)sfwordnr + 1, false);
+  nrline = (char_u *)ml_get_buf(slang->sl_sugbuf, (linenr_T)sfwordnr + 1, false);
   orgnr = 0;
   while (*nrline != NUL) {
     // The wordnr was stored in a minimal nr of bytes as an offset to the
diff --git a/src/nvim/statusline.c b/src/nvim/statusline.c
index 9b441ba0a9..5f686ef96f 100644
--- a/src/nvim/statusline.c
+++ b/src/nvim/statusline.c
@@ -426,7 +426,7 @@ void win_redr_custom(win_T *wp, bool draw_winbar, bool draw_ruler)
   int len;
   int fillchar;
   char buf[MAXPATHL];
-  char_u *stl;
+  char *stl;
   char *p;
   stl_hlrec_t *hltab;
   StlClickRecord *tabtab;
@@ -448,14 +448,14 @@ void win_redr_custom(win_T *wp, bool draw_winbar, bool draw_ruler)
   // setup environment for the task at hand
   if (wp == NULL) {
     // Use 'tabline'.  Always at the first line of the screen.
-    stl = (char_u *)p_tal;
+    stl = p_tal;
     row = 0;
     fillchar = ' ';
     attr = HL_ATTR(HLF_TPF);
     maxwidth = Columns;
     use_sandbox = was_set_insecurely(wp, "tabline", 0);
   } else if (draw_winbar) {
-    stl = (char_u *)((*wp->w_p_wbr != NUL) ? wp->w_p_wbr : p_wbr);
+    stl = ((*wp->w_p_wbr != NUL) ? wp->w_p_wbr : p_wbr);
     row = -1;  // row zero is first row of text
     col = 0;
     grid = &wp->w_grid;
@@ -491,19 +491,19 @@ void win_redr_custom(win_T *wp, bool draw_winbar, bool draw_ruler)
     }
 
     if (draw_ruler) {
-      stl = (char_u *)p_ruf;
+      stl = p_ruf;
       // advance past any leading group spec - implicit in ru_col
       if (*stl == '%') {
         if (*++stl == '-') {
           stl++;
         }
-        if (atoi((char *)stl)) {
+        if (atoi(stl)) {
           while (ascii_isdigit(*stl)) {
             stl++;
           }
         }
         if (*stl++ != '(') {
-          stl = (char_u *)p_ruf;
+          stl = p_ruf;
         }
       }
       col = ru_col - (Columns - maxwidth);
@@ -522,9 +522,9 @@ void win_redr_custom(win_T *wp, bool draw_winbar, bool draw_ruler)
       use_sandbox = was_set_insecurely(wp, "rulerformat", 0);
     } else {
       if (*wp->w_p_stl != NUL) {
-        stl = (char_u *)wp->w_p_stl;
+        stl = wp->w_p_stl;
       } else {
-        stl = (char_u *)p_stl;
+        stl = p_stl;
       }
       use_sandbox = was_set_insecurely(wp, "statusline", *wp->w_p_stl == NUL ? 0 : OPT_LOCAL);
     }
@@ -544,9 +544,9 @@ void win_redr_custom(win_T *wp, bool draw_winbar, bool draw_ruler)
 
   // Make a copy, because the statusline may include a function call that
   // might change the option value and free the memory.
-  stl = vim_strsave(stl);
+  stl = xstrdup(stl);
   width =
-    build_stl_str_hl(ewp, buf, sizeof(buf), (char *)stl, use_sandbox,
+    build_stl_str_hl(ewp, buf, sizeof(buf), stl, use_sandbox,
                      fillchar, maxwidth, &hltab, &tabtab);
   xfree(stl);
   ewp->w_p_crb = p_crb_save;
@@ -711,7 +711,7 @@ int build_stl_str_hl(win_T *wp, char *out, size_t outlen, char *fmt, int use_san
   }
 
   // Get line & check if empty (cursorpos will show "0-1").
-  const char *line_ptr = (char *)ml_get_buf(wp->w_buffer, lnum, false);
+  const char *line_ptr = ml_get_buf(wp->w_buffer, lnum, false);
   bool empty_line = (*line_ptr == NUL);
 
   // Get the byte value now, in case we need it below. This is more
diff --git a/src/nvim/strings.c b/src/nvim/strings.c
index d7a0472cbf..04f9311d7e 100644
--- a/src/nvim/strings.c
+++ b/src/nvim/strings.c
@@ -49,13 +49,6 @@
 #include "nvim/vim.h"
 #include "nvim/window.h"
 
-/// Copy "string" into newly allocated memory.
-char_u *vim_strsave(const char_u *string)
-  FUNC_ATTR_NONNULL_RET FUNC_ATTR_MALLOC FUNC_ATTR_NONNULL_ALL
-{
-  return (char_u *)xstrdup((char *)string);
-}
-
 /// Copy up to `len` bytes of `string` into newly allocated memory and
 /// terminate with a NUL. The allocated memory always has size `len + 1`, even
 /// when `string` is shorter.
@@ -292,11 +285,11 @@ char_u *vim_strsave_shellescape(const char_u *string, bool do_special, bool do_n
 char_u *vim_strsave_up(const char_u *string)
   FUNC_ATTR_NONNULL_RET FUNC_ATTR_MALLOC FUNC_ATTR_NONNULL_ALL
 {
-  char_u *p1;
+  char *p1;
 
-  p1 = vim_strsave(string);
-  vim_strup(p1);
-  return p1;
+  p1 = xstrdup((char *)string);
+  vim_strup((char_u *)p1);
+  return (char_u *)p1;
 }
 
 /// Like xstrnsave(), but make all characters uppercase.
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index fedd053e88..1daeebd7b9 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -2468,7 +2468,7 @@ static void find_endpos(int idx, lpos_T *startpos, lpos_T *m_endpos, lpos_T *hl_
           break;
         }
 
-        line = ml_get_buf(syn_buf, startpos->lnum, false);
+        line = (char_u *)ml_get_buf(syn_buf, startpos->lnum, false);
         int line_len = (int)STRLEN(line);
 
         // take care of an empty match or negative offset
@@ -2604,7 +2604,7 @@ static void syn_add_end_off(lpos_T *result, regmmatch_T *regmatch, synpat_T *spp
   if (result->lnum > syn_buf->b_ml.ml_line_count) {
     col = 0;
   } else if (off != 0) {
-    base = ml_get_buf(syn_buf, result->lnum, false);
+    base = (char_u *)ml_get_buf(syn_buf, result->lnum, false);
     p = base + col;
     if (off > 0) {
       while (off-- > 0 && *p != NUL) {
@@ -2649,7 +2649,7 @@ static void syn_add_start_off(lpos_T *result, regmmatch_T *regmatch, synpat_T *s
     col = (int)STRLEN(ml_get_buf(syn_buf, result->lnum, false));
   }
   if (off != 0) {
-    base = ml_get_buf(syn_buf, result->lnum, false);
+    base = (char_u *)ml_get_buf(syn_buf, result->lnum, false);
     p = base + col;
     if (off > 0) {
       while (off-- && *p != NUL) {
@@ -2668,7 +2668,7 @@ static void syn_add_start_off(lpos_T *result, regmmatch_T *regmatch, synpat_T *s
 /// Get current line in syntax buffer.
 static char *syn_getcurline(void)
 {
-  return (char *)ml_get_buf(syn_buf, current_lnum, false);
+  return ml_get_buf(syn_buf, current_lnum, false);
 }
 
 // Call vim_regexec() to find a match with "rmp" in "syn_buf".
diff --git a/src/nvim/tag.c b/src/nvim/tag.c
index 04154384af..8be752239c 100644
--- a/src/nvim/tag.c
+++ b/src/nvim/tag.c
@@ -96,7 +96,7 @@ static char *mt_names[MT_COUNT/2] =
 { "FSC", "F C", "F  ", "FS ", " SC", "  C", "   ", " S " };
 
 #define NOTAGFILE       99              // return value for jumpto_tag
-static char_u *nofile_fname = NULL;   // fname for NOTAGFILE error
+static char *nofile_fname = NULL;       // fname for NOTAGFILE error
 
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "tag.c.generated.h"
@@ -109,7 +109,7 @@ static char_u *recurmsg
 static char_u *tfu_inv_ret_msg
   = (char_u *)N_("E987: invalid return value from tagfunc");
 
-static char_u *tagmatchname = NULL;   // name of last used tag
+static char *tagmatchname = NULL;   // name of last used tag
 
 // Tag for preview window is remembered separately, to avoid messing up the
 // normal tagstack.
@@ -142,7 +142,7 @@ static int tfu_in_use = false;  // disallow recursive call of tagfunc
 /// @param tag  tag (pattern) to jump to
 /// @param forceit  :ta with !
 /// @param verbose  print "tag not found" message
-bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
+bool do_tag(char *tag, int type, int count, int forceit, int verbose)
 {
   taggy_T *tagstack = curwin->w_tagstack;
   int tagstackidx = curwin->w_tagstackidx;
@@ -195,7 +195,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
   }
 
   prev_num_matches = num_matches;
-  free_string_option((char *)nofile_fname);
+  free_string_option(nofile_fname);
   nofile_fname = NULL;
 
   clearpos(&saved_fmark.mark);          // shutup gcc 4.0
@@ -208,7 +208,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
     new_tag = true;
     if (g_do_tagpreview != 0) {
       tagstack_clear_entry(&ptag_entry);
-      ptag_entry.tagname = (char *)vim_strsave(tag);
+      ptag_entry.tagname = xstrdup(tag);
     }
   } else {
     if (g_do_tagpreview != 0) {
@@ -232,7 +232,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
           cur_fnum = ptag_entry.cur_fnum;
         } else {
           tagstack_clear_entry(&ptag_entry);
-          ptag_entry.tagname = (char *)vim_strsave(tag);
+          ptag_entry.tagname = xstrdup(tag);
         }
       } else {
         // If the last used entry is not at the top, delete all tag
@@ -252,7 +252,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
         }
 
         // put the tag name in the tag stack
-        tagstack[tagstackidx].tagname = (char *)vim_strsave(tag);
+        tagstack[tagstackidx].tagname = xstrdup(tag);
 
         curwin->w_tagstacklen = tagstacklen;
 
@@ -419,13 +419,13 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
   // Repeat searching for tags, when a file has not been found.
   for (;;) {
     int other_name;
-    char_u *name;
+    char *name;
 
     // When desired match not found yet, try to find it (and others).
     if (use_tagstack) {
-      name = (char_u *)tagstack[tagstackidx].tagname;
+      name = tagstack[tagstackidx].tagname;
     } else if (g_do_tagpreview != 0) {
-      name = (char_u *)ptag_entry.tagname;
+      name = ptag_entry.tagname;
     } else {
       name = tag;
     }
@@ -435,7 +435,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
         || other_name) {
       if (other_name) {
         xfree(tagmatchname);
-        tagmatchname = vim_strsave(name);
+        tagmatchname = xstrdup(name);
       }
 
       if (type == DT_SELECT || type == DT_JUMP
@@ -466,7 +466,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
         flags |= TAG_NO_TAGFUNC;
       }
 
-      if (find_tags((char *)name, &new_num_matches, &new_matches, flags,
+      if (find_tags(name, &new_num_matches, &new_matches, flags,
                     max_num_matches, (char *)buf_ffname) == OK
           && new_num_matches < max_num_matches) {
         max_num_matches = MAXCOL;  // If less than max_num_matches
@@ -522,7 +522,7 @@ bool do_tag(char_u *tag, int type, int count, int forceit, int verbose)
         print_tag_list(new_tag, use_tagstack, num_matches, matches);
         ask_for_selection = true;
       } else if (type == DT_LTAG) {
-        if (add_llist_tags(tag, num_matches, matches) == FAIL) {
+        if (add_llist_tags((char_u *)tag, num_matches, matches) == FAIL) {
           goto end_do_tag;
         }
 
@@ -1172,7 +1172,7 @@ static int find_tagfunc_tags(char_u *pat, garray_T *ga, int *match_count, int fl
   taglist = rettv.vval.v_list;
 
   TV_LIST_ITER_CONST(taglist, li, {
-    char_u *res_name;
+    char *res_name;
     char_u *res_fname;
     char_u *res_cmd;
     char_u *res_kind;
@@ -1200,7 +1200,7 @@ static int find_tagfunc_tags(char_u *pat, garray_T *ga, int *match_count, int fl
 
       len += strlen(tv->vval.v_string) + 1;   // Space for "\tVALUE"
       if (!STRCMP(dict_key, "name")) {
-        res_name = (char_u *)tv->vval.v_string;
+        res_name = tv->vval.v_string;
         continue;
       }
       if (!STRCMP(dict_key, "filename")) {
@@ -1230,10 +1230,10 @@ static int find_tagfunc_tags(char_u *pat, garray_T *ga, int *match_count, int fl
       break;
     }
 
-    char_u *const mfp = name_only ? vim_strsave(res_name) : xmalloc(len + 2);
+    char *const mfp = name_only ? xstrdup(res_name) : xmalloc(len + 2);
 
     if (!name_only) {
-      char_u *p = mfp;
+      char_u *p = (char_u *)mfp;
 
       *p++ = MT_GL_OTH + 1;   // mtt
       *p++ = TAG_SEP;     // no tag file name
@@ -2242,13 +2242,13 @@ static garray_T tag_fnames = GA_EMPTY_INIT_VALUE;
 // 'runtimepath' doc directories.
 static void found_tagfile_cb(char *fname, void *cookie)
 {
-  char_u *const tag_fname = vim_strsave((char_u *)fname);
+  char *const tag_fname = xstrdup(fname);
 
 #ifdef BACKSLASH_IN_FILENAME
   slash_adjust(tag_fname);
 #endif
-  simplify_filename(tag_fname);
-  GA_APPEND(char_u *, &tag_fnames, tag_fname);
+  simplify_filename((char_u *)tag_fname);
+  GA_APPEND(char *, &tag_fnames, tag_fname);
 }
 
 #if defined(EXITFREE)
@@ -2319,8 +2319,8 @@ int get_tagfname(tagname_T *tnp, int first, char *buf)
   if (first) {
     // Init.  We make a copy of 'tags', because autocommands may change
     // the value without notifying us.
-    tnp->tn_tags = vim_strsave((*curbuf->b_p_tags != NUL) ? (char_u *)curbuf->b_p_tags : p_tags);
-    tnp->tn_np = (char *)tnp->tn_tags;
+    tnp->tn_tags = xstrdup((*curbuf->b_p_tags != NUL) ? curbuf->b_p_tags : (char *)p_tags);
+    tnp->tn_np = tnp->tn_tags;
   }
 
   // Loop until we have found a file name that can be used.
@@ -2550,7 +2550,8 @@ static char_u *tag_full_fname(tagptrs_T *tagp)
 {
   int c = *tagp->fname_end;
   *tagp->fname_end = NUL;
-  char_u *fullname = expand_tag_fname(tagp->fname, tagp->tag_fname, false);
+  char_u *fullname =
+    (char_u *)expand_tag_fname((char *)tagp->fname, (char *)tagp->tag_fname, false);
   *tagp->fname_end = (char_u)c;
 
   return fullname;
@@ -2573,7 +2574,7 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
   char_u *pbuf;                    // search pattern buffer
   char_u *pbuf_end;
   char_u *tofree_fname = NULL;
-  char_u *fname;
+  char *fname;
   tagptrs_T tagp;
   int retval = FAIL;
   int getfile_result = GETFILE_UNUSED;
@@ -2596,7 +2597,7 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
 
   // truncate the file name, so it can be used as a string
   *tagp.fname_end = NUL;
-  fname = tagp.fname;
+  fname = (char *)tagp.fname;
 
   // copy the command to pbuf[], remove trailing CR/NL
   str = tagp.command;
@@ -2619,18 +2620,17 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
 
   // Expand file name, when needed (for environment variables).
   // If 'tagrelative' option set, may change file name.
-  fname = expand_tag_fname(fname, tagp.tag_fname, true);
-  tofree_fname = fname;         // free() it later
+  fname = expand_tag_fname(fname, (char *)tagp.tag_fname, true);
+  tofree_fname = (char_u *)fname;         // free() it later
 
   // Check if the file with the tag exists before abandoning the current
   // file.  Also accept a file name for which there is a matching BufReadCmd
   // autocommand event (e.g., http://sys/file).
-  if (!os_path_exists((char *)fname)
-      && !has_autocmd(EVENT_BUFREADCMD, (char *)fname,
-                      NULL)) {
+  if (!os_path_exists(fname)
+      && !has_autocmd(EVENT_BUFREADCMD, fname, NULL)) {
     retval = NOTAGFILE;
     xfree(nofile_fname);
-    nofile_fname = vim_strsave(fname);
+    nofile_fname = xstrdup(fname);
     goto erret;
   }
 
@@ -2644,8 +2644,8 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
     // entering it (autocommands) so turn the tag filename
     // into a fullpath
     if (!curwin->w_p_pvw) {
-      full_fname = (char_u *)FullName_save((char *)fname, false);
-      fname = full_fname;
+      full_fname = (char_u *)FullName_save(fname, false);
+      fname = (char *)full_fname;
 
       // Make the preview window the current window.
       // Open a preview window when needed.
@@ -2656,7 +2656,7 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
   // If it was a CTRL-W CTRL-] command split window now.  For ":tab tag"
   // open a new tab page.
   if (postponed_split && (swb_flags & (SWB_USEOPEN | SWB_USETAB))) {
-    buf_T *const existing_buf = buflist_findname_exp((char *)fname);
+    buf_T *const existing_buf = buflist_findname_exp(fname);
 
     if (existing_buf != NULL) {
       const win_T *wp = NULL;
@@ -2701,7 +2701,7 @@ static int jumpto_tag(const char_u *lbuf_arg, int forceit, int keep_help)
   if (getfile_result == GETFILE_UNUSED) {
     // Careful: getfile() may trigger autocommands and call jumpto_tag()
     // recursively.
-    getfile_result = getfile(0, (char *)fname, NULL, true, (linenr_T)0, forceit);
+    getfile_result = getfile(0, fname, NULL, true, (linenr_T)0, forceit);
   }
   keep_help_flag = false;
 
@@ -2867,18 +2867,19 @@ erret:
   return retval;
 }
 
-// If "expand" is true, expand wildcards in fname.
-// If 'tagrelative' option set, change fname (name of file containing tag)
-// according to tag_fname (name of tag file containing fname).
-// Returns a pointer to allocated memory.
-static char_u *expand_tag_fname(char_u *fname, char_u *const tag_fname, const bool expand)
+/// If "expand" is true, expand wildcards in fname.
+/// If 'tagrelative' option set, change fname (name of file containing tag)
+/// according to tag_fname (name of tag file containing fname).
+///
+/// @return  a pointer to allocated memory.
+static char *expand_tag_fname(char *fname, char *const tag_fname, const bool expand)
 {
-  char_u *p;
-  char_u *expanded_fname = NULL;
+  char *p;
+  char *expanded_fname = NULL;
   expand_T xpc;
 
   // Expand file name (for environment variables) when needed.
-  if (expand && path_has_wildcard((char *)fname)) {
+  if (expand && path_has_wildcard(fname)) {
     ExpandInit(&xpc);
     xpc.xp_context = EXPAND_FILES;
     expanded_fname = ExpandOne(&xpc, fname, NULL,
@@ -2888,18 +2889,18 @@ static char_u *expand_tag_fname(char_u *fname, char_u *const tag_fname, const bo
     }
   }
 
-  char_u *retval;
+  char *retval;
   if ((p_tr || curbuf->b_help)
-      && !vim_isAbsName(fname)
-      && (p = (char_u *)path_tail((char *)tag_fname)) != tag_fname) {
+      && !vim_isAbsName((char_u *)fname)
+      && (p = path_tail(tag_fname)) != tag_fname) {
     retval = xmalloc(MAXPATHL);
     STRCPY(retval, tag_fname);
     STRLCPY(retval + (p - tag_fname), fname,
             MAXPATHL - (p - tag_fname));
     // Translate names like "src/a/../b/file.c" into "src/b/file.c".
-    simplify_filename(retval);
+    simplify_filename((char_u *)retval);
   } else {
-    retval = vim_strsave(fname);
+    retval = xstrdup(fname);
   }
 
   xfree(expanded_fname);
@@ -2922,7 +2923,7 @@ static int test_for_current(char *fname, char *fname_end, char *tag_fname, char
       c = (unsigned char)(*fname_end);
       *fname_end = NUL;
     }
-    char *fullname = (char *)expand_tag_fname((char_u *)fname, (char_u *)tag_fname, true);
+    char *fullname = expand_tag_fname(fname, tag_fname, true);
     retval = (path_full_compare(fullname, buf_ffname, true, true) & kEqualFiles);
     xfree(fullname);
     *fname_end = (char)c;
diff --git a/src/nvim/tag.h b/src/nvim/tag.h
index 0b4039afb6..7f2ef8d6d7 100644
--- a/src/nvim/tag.h
+++ b/src/nvim/tag.h
@@ -34,7 +34,7 @@
 
 // Structure used for get_tagfname().
 typedef struct {
-  char_u *tn_tags;         // value of 'tags' when starting
+  char *tn_tags;           // value of 'tags' when starting
   char *tn_np;             // current position in tn_tags
   int tn_did_filefind_init;
   int tn_hf_idx;
diff --git a/src/nvim/textformat.c b/src/nvim/textformat.c
index 6e69fb95c8..5c53f84700 100644
--- a/src/nvim/textformat.c
+++ b/src/nvim/textformat.c
@@ -97,7 +97,7 @@ void internal_format(int textwidth, int second_indent, int flags, bool format_on
     colnr_T len;
     colnr_T virtcol;
     int orig_col = 0;
-    char_u *saved_text = NULL;
+    char *saved_text = NULL;
     colnr_T col;
     colnr_T end_col;
     bool did_do_comment = false;
@@ -353,7 +353,7 @@ void internal_format(int textwidth, int second_indent, int flags, bool format_on
     if (State & VREPLACE_FLAG) {
       // In MODE_VREPLACE state, we will backspace over the text to be
       // wrapped, so save a copy now to put on the next line.
-      saved_text = vim_strsave(get_cursor_pos_ptr());
+      saved_text = xstrdup(get_cursor_pos_ptr());
       curwin->w_cursor.col = orig_col;
       saved_text[startcol] = NUL;
 
@@ -425,7 +425,7 @@ void internal_format(int textwidth, int second_indent, int flags, bool format_on
     if (State & VREPLACE_FLAG) {
       // In MODE_VREPLACE state we have backspaced over the text to be
       // moved, now we re-insert it into the new line.
-      ins_bytes((char *)saved_text);
+      ins_bytes(saved_text);
       xfree(saved_text);
     } else {
       // Check if cursor is not past the NUL off the line, cindent
@@ -508,13 +508,13 @@ static bool ends_in_white(linenr_T lnum)
 /// @param lnum  The first line.  White-space is ignored.
 ///
 /// @note the whole of 'leader1' must match 'leader2_len' characters from 'leader2'.
-static bool same_leader(linenr_T lnum, int leader1_len, char_u *leader1_flags, int leader2_len,
-                        char_u *leader2_flags)
+static bool same_leader(linenr_T lnum, int leader1_len, char *leader1_flags, int leader2_len,
+                        char *leader2_flags)
 {
   int idx1 = 0, idx2 = 0;
-  char_u *p;
-  char_u *line1;
-  char_u *line2;
+  char *p;
+  char *line1;
+  char *line2;
 
   if (leader1_len == 0) {
     return leader2_len == 0;
@@ -552,9 +552,9 @@ static bool same_leader(linenr_T lnum, int leader1_len, char_u *leader1_flags, i
 
   // Get current line and next line, compare the leaders.
   // The first line has to be saved, only one line can be locked at a time.
-  line1 = vim_strsave((char_u *)ml_get(lnum));
+  line1 = xstrdup(ml_get(lnum));
   for (idx1 = 0; ascii_iswhite(line1[idx1]); idx1++) {}
-  line2 = (char_u *)ml_get(lnum + 1);
+  line2 = ml_get(lnum + 1);
   for (idx2 = 0; idx2 < leader2_len; idx2++) {
     if (!ascii_iswhite(line2[idx2])) {
       if (line1[idx1++] != line2[idx2]) {
@@ -605,8 +605,8 @@ static bool paragraph_start(linenr_T lnum)
   if (has_format_option(FO_Q_NUMBER) && (get_number_indent(lnum) > 0)) {
     return true;                // numbered item starts in "lnum".
   }
-  if (!same_leader(lnum - 1, leader_len, leader_flags,
-                   next_leader_len, next_leader_flags)) {
+  if (!same_leader(lnum - 1, leader_len, (char *)leader_flags,
+                   next_leader_len, (char *)next_leader_flags)) {
     return true;                // change of comment leader.
   }
   return false;
@@ -1018,9 +1018,9 @@ void format_lines(linenr_T line_count, bool avoid_fex)
       // When the comment leader changes, it's the end of the paragraph.
       if (curwin->w_cursor.lnum >= curbuf->b_ml.ml_line_count
           || !same_leader(curwin->w_cursor.lnum,
-                          leader_len, leader_flags,
+                          leader_len, (char *)leader_flags,
                           next_leader_len,
-                          next_leader_flags)) {
+                          (char *)next_leader_flags)) {
         // Special case: If the next line starts with a line comment
         // and this line has a line comment after some text, the
         // paragraph doesn't really end.
diff --git a/src/nvim/textobject.c b/src/nvim/textobject.c
index 6863b40599..621efa44cf 100644
--- a/src/nvim/textobject.c
+++ b/src/nvim/textobject.c
@@ -1157,7 +1157,7 @@ again:
 
   // Search for matching "</aaa>".  First isolate the "aaa".
   inc_cursor();
-  p = get_cursor_pos_ptr();
+  p = (char_u *)get_cursor_pos_ptr();
   for (cp = p;
        *cp != NUL && *cp != '>' && !ascii_iswhite(*cp);
        MB_PTR_ADV(cp)) {}
@@ -1196,7 +1196,7 @@ again:
       }
     }
   } else {
-    char_u *c = get_cursor_pos_ptr();
+    char_u *c = (char_u *)get_cursor_pos_ptr();
     // Exclude the '<' of the end tag.
     // If the closing tag is on new line, do not decrement cursor, but make
     // operation exclusive, so that the linefeed will be selected
diff --git a/src/nvim/undo.c b/src/nvim/undo.c
index 5f086df4e9..ab14f4d4ea 100644
--- a/src/nvim/undo.c
+++ b/src/nvim/undo.c
@@ -567,7 +567,7 @@ int u_savecommon(buf_T *buf, linenr_T top, linenr_T bot, linenr_T newbot, int re
         u_freeentry(uep, i);
         return FAIL;
       }
-      uep->ue_array[i] = u_save_line_buf(buf, lnum++);
+      uep->ue_array[i] = (char_u *)u_save_line_buf(buf, lnum++);
     }
   } else {
     uep->ue_array = NULL;
@@ -621,7 +621,7 @@ void u_compute_hash(buf_T *buf, char_u *hash)
   context_sha256_T ctx;
   sha256_start(&ctx);
   for (linenr_T lnum = 1; lnum <= buf->b_ml.ml_line_count; lnum++) {
-    char_u *p = ml_get_buf(buf, lnum, false);
+    char_u *p = (char_u *)ml_get_buf(buf, lnum, false);
     sha256_update(&ctx, p, (uint32_t)(STRLEN(p) + 1));
   }
   sha256_finish(&ctx, hash);
@@ -2643,7 +2643,7 @@ void ex_undolist(exarg_T *eap)
         }
         vim_snprintf_add((char *)IObuff, IOSIZE, "  %3ld", uhp->uh_save_nr);
       }
-      GA_APPEND(char_u *, &ga, vim_strsave(IObuff));
+      GA_APPEND(char *, &ga, xstrdup((char *)IObuff));
     }
 
     uhp->uh_walk = mark;
@@ -3027,16 +3027,16 @@ void u_blockfree(buf_T *buf)
 /// @param lnum the line to copy
 static char_u *u_save_line(linenr_T lnum)
 {
-  return u_save_line_buf(curbuf, lnum);
+  return (char_u *)u_save_line_buf(curbuf, lnum);
 }
 
 /// Allocate memory and copy line into it
 ///
 /// @param lnum line to copy
 /// @param buf buffer to copy from
-static char_u *u_save_line_buf(buf_T *buf, linenr_T lnum)
+static char *u_save_line_buf(buf_T *buf, linenr_T lnum)
 {
-  return vim_strsave(ml_get_buf(buf, lnum, false));
+  return xstrdup(ml_get_buf(buf, lnum, false));
 }
 
 /// Check if the 'modified' flag is set, or 'ff' has changed (only need to
diff --git a/test/unit/message_spec.lua b/test/unit/message_spec.lua
index 7e92b5c857..549eff6e03 100644
--- a/test/unit/message_spec.lua
+++ b/test/unit/message_spec.lua
@@ -22,7 +22,7 @@ describe('trunc_string', function()
   local function test_copy(s, expected, room)
     room = room and room or 20
     local buf = cimp.xmalloc(ffi.sizeof('char_u') * buflen)
-    local str = cimp.vim_strsave(to_cstr(s))
+    local str = cimp.xstrdup(to_cstr(s))
     cimp.trunc_string(str, buf, room, buflen)
     eq(expected, ffi.string(buf))
     cimp.xfree(buf)