vim-patch:7.4.1051

Problem:    Segfault when unletting "count".
Solution:   Check for readonly and locked first. (Dominique Pelle)
            Add a test.

https://github.com/vim/vim/commit/af8af8bfac5792fa64efbc524032d568cc7754f7

1 files changed, 15 insertions, 12 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 3cd53b841d..425c3d3ed5 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -2973,24 +2973,27 @@ int do_unlet(char_u *name, int forceit)
   ht = find_var_ht_dict(name, &varname, &dict);
 
   if (ht != NULL && *varname != NUL) {
-    if (ht == &globvarht) {
-      d = &globvardict;
-    } else if (current_funccal != NULL
-               && ht == &current_funccal->l_vars.dv_hashtab) {
-      d = &current_funccal->l_vars;
-    } else {
-      di = find_var_in_ht(ht, *name, (char_u *)"", false);
-      d = di->di_tv.vval.v_dict;
-    }
-
     hi = hash_find(ht, varname);
     if (!HASHITEM_EMPTY(hi)) {
       di = HI2DI(hi);
       if (var_check_fixed(di->di_flags, name, false)
-          || var_check_ro(di->di_flags, name, false)
-          || tv_check_lock(d->dv_lock, name, false)) {
+          || var_check_ro(di->di_flags, name, false)) {
         return FAIL;
       }
+
+      if (ht == &globvarht) {
+        d = &globvardict;
+      } else if (current_funccal != NULL
+                 && ht == &current_funccal->l_vars.dv_hashtab) {
+        d = &current_funccal->l_vars;
+      } else {
+        di = find_var_in_ht(ht, *name, (char_u *)"", false);
+        d = di->di_tv.vval.v_dict;
+      }
+      if (d == NULL || tv_check_lock(d->dv_lock, name, false)) {
+        return FAIL;
+      }
+
       typval_T oldtv;
       bool watched = is_watched(dict);