patch 8.1.0804: crash when setting v:errmsg to empty list
Problem: Crash when setting v:errmsg to empty list. (Jaon Franklin)
Solution: Separate getting value and assigning result.
diff --git a/src/eval.c b/src/eval.c
index f111dc4..efa168e 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -7892,9 +7892,16 @@
{
if (v->di_tv.v_type == VAR_STRING)
{
- vim_free(v->di_tv.vval.v_string);
+ VIM_CLEAR(v->di_tv.vval.v_string);
if (copy || tv->v_type != VAR_STRING)
- v->di_tv.vval.v_string = vim_strsave(tv_get_string(tv));
+ {
+ char_u *val = tv_get_string(tv);
+
+ // Careful: when assigning to v:errmsg and tv_get_string()
+ // causes an error message the variable will alrady be set.
+ if (v->di_tv.vval.v_string == NULL)
+ v->di_tv.vval.v_string = vim_strsave(val);
+ }
else
{
/* Take over the string to avoid an extra alloc/free. */