patch 9.0.1830: Vim9: crash when accessing a null object Commit: https://github.com/vim/vim/commit/d7085a06358c22250a27186bb7d52112ed4addd1 Author: Gianmaria Bajo <mg1979.git@gmail.com> Date: Thu Aug 31 18:15:26 2023 +0200 patch 9.0.1830: Vim9: crash when accessing a null object Problem: Vim9: crash when accessing a null object Solution: Check accessing a NULL object in def function An object is NULL when the variable is declared, but the constructor isn't called. Accessing/setting a member on the object crashed Vim. Note: this happens inside def functions, at script level things work differently. Accessing a NULL object member results in E1360 (correctly), while setting a value on it results in E1012 (type mismatch) so there's still something to fix. closes: #12973 Signed-off-by: Christian Brabandt <cb@256bit.org> Co-authored-by: Gianmaria Bajo <mg1979.git@gmail.com>

--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -2147,7 +2147,14 @@ execute_storeindex(isn_T *iptr, ectx_T *
     // -1 dict, list, blob or object
     tv = STACK_TV_BOT(-3);
     SOURCING_LNUM = iptr->isn_lnum;
-    if (dest_type == VAR_ANY)
+
+    // Make sure an object has been initialized
+    if (dest_type == VAR_OBJECT && tv_dest->vval.v_object == NULL)
+    {
+	emsg(_(e_using_null_object));
+	status = FAIL;
+    }
+    else if (dest_type == VAR_ANY)
     {
 	dest_type = tv_dest->v_type;
 	if (dest_type == VAR_DICT)