# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1651833004 -7200
# Node ID d59c8dc8be201b2a8cc192545d5da730b4cdb5e9
# Parent  9ef5ee193725f2433bcb2dc0b502d1fb0964a7c6
patch 8.2.4880: Vim9: misplaced elseif causes invalid memory access

Commit: https://github.com/vim/vim/commit/434725cc4cbbadafc82954178f55864741455cdb
Author: Bram Moolenaar <Bram@vim.org>
Date:   Fri May 6 11:27:52 2022 +0100

    patch 8.2.4880: Vim9: misplaced elseif causes invalid memory access

    Problem:    Vim9: misplaced elseif causes invalid memory access.
    Solution:   Check cs_idx not to be negative.

diff --git a/src/ex_eval.c b/src/ex_eval.c
--- a/src/ex_eval.c
+++ b/src/ex_eval.c
@@ -1124,10 +1124,13 @@ ex_else(exarg_T *eap)
 	skip = TRUE;
     }
 
-    // Variables declared in the previous block can no longer be
-    // used.  Needs to be done before setting "cs_flags".
-    leave_block(cstack);
-    enter_block(cstack);
+    if (cstack->cs_idx >= 0)
+    {
+	// Variables declared in the previous block can no longer be
+	// used.  Needs to be done before setting "cs_flags".
+	leave_block(cstack);
+	enter_block(cstack);
+    }
 
     // if skipping or the ":if" was TRUE, reset ACTIVE, otherwise set it
     if (skip || cstack->cs_flags[cstack->cs_idx] & CSF_TRUE)
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -747,6 +747,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4880,
+/**/
     4879,
 /**/
     4878,