build: fix gcc warnings #10568

gcc version 8.3.0 (Debian 8.3.0-6)

    ../src/nvim/ex_docmd.c: In function ‘commands_array’:
    ../src/nvim/ex_docmd.c:10192:36: warning: ‘%ld’ directive output may be truncated writing between 1 and 19 bytes into a region of size 10 [-Wformat-truncation=]
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
                                        ^~~
    ../src/nvim/ex_docmd.c:10192:37: note: format string is defined here
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
    ../src/nvim/ex_docmd.c:10192:36: note: directive argument in the range [0, 9223372036854775807]
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
                                        ^~~
    ../src/nvim/ex_docmd.c:10192:9: note: ‘snprintf’ output between 2 and 20 bytes into a destination of size 10
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../src/nvim/ex_docmd.c:10205:36: warning: ‘%ld’ directive output may be truncated writing between 1 and 19 bytes into a region of size 10 [-Wformat-truncation=]
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
                                        ^~~
    ../src/nvim/ex_docmd.c:10205:37: note: format string is defined here
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
    ../src/nvim/ex_docmd.c:10205:36: note: directive argument in the range [0, 9223372036854775807]
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
                                        ^~~
    ../src/nvim/ex_docmd.c:10205:9: note: ‘snprintf’ output between 2 and 20 bytes into a destination of size 10
             snprintf(str, sizeof(str), "%" PRId64, (int64_t)cmd->uc_def);
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../src/nvim/spell.c: In function ‘did_set_spelllang’:
    ../src/nvim/spell.c:1631:61: warning: ‘%s’ directive output may be truncated writing up to 254 bytes into a region of size 84 [-Wformat-truncation=]
                    "autocmd VimEnter * call spellfile#LoadFile('%s')|set spell",
                                                                 ^~
    ../src/nvim/spell.c:2063:25:
             spell_load_lang(lang);
                             ~~~~                                 
    ../src/nvim/spell.c:1630:7: note: ‘snprintf’ output between 57 and 311 bytes into a destination of size 128
           snprintf(autocmd_buf, sizeof(autocmd_buf),
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                    "autocmd VimEnter * call spellfile#LoadFile('%s')|set spell",
                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                    lang);
                    ~~~~~
    ../src/nvim/window.c: In function ‘win_rotate’:
    ../src/nvim/window.c:1780:22: warning: ‘wp2’ may be used uninitialized in this function [-Wmaybe-uninitialized]
       wp2->w_pos_changed = true;
                          ^
    ../src/nvim/window.c:1779:22: warning: ‘wp1’ may be used uninitialized in this function [-Wmaybe-uninitialized]
       wp1->w_pos_changed = true;

3 files changed, 3 insertions, 3 deletions

diff --git a/src/nvim/ex_docmd.c b/src/nvim/ex_docmd.c
index af4f34d907..af5635ddba 100644
--- a/src/nvim/ex_docmd.c
+++ b/src/nvim/ex_docmd.c
@@ -10172,7 +10172,7 @@ Dictionary commands_array(buf_T *buf)
   Dictionary rv = ARRAY_DICT_INIT;
   Object obj = NIL;
   (void)obj;  // Avoid "dead assignment" warning.
-  char str[10];
+  char str[20];
   garray_T *gap = (buf == NULL) ? &ucmds : &buf->b_ucmds;
 
   for (int i = 0; i < gap->ga_len; i++) {
diff --git a/src/nvim/spell.c b/src/nvim/spell.c
index b5885e65f3..66eb4ac3c6 100644
--- a/src/nvim/spell.c
+++ b/src/nvim/spell.c
@@ -1626,7 +1626,7 @@ static void spell_load_lang(char_u *lang)
     if (starting) {
       // Prompt the user at VimEnter if spell files are missing. #3027
       // Plugins aren't loaded yet, so spellfile.vim cannot handle this case.
-      char autocmd_buf[128] = { 0 };
+      char autocmd_buf[512] = { 0 };
       snprintf(autocmd_buf, sizeof(autocmd_buf),
                "autocmd VimEnter * call spellfile#LoadFile('%s')|set spell",
                lang);
diff --git a/src/nvim/window.c b/src/nvim/window.c
index 377d712a50..22a8969b88 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -1713,7 +1713,7 @@ static void win_rotate(bool upwards, int count)
     return;
   }
 
-  if (firstwin == curwin && lastwin_nofloating() == curwin) {
+  if (count <= 0 || (firstwin == curwin && lastwin_nofloating() == curwin)) {
     // nothing to do
     beep_flush();
     return;