vim-patch:7.4.2357 (#6354)

Problem:    Attempt to read history entry while not initialized.
Solution:   Skip when the index is negative.

46643713dc

src/nvim/ex_getln.c

@@ -4677,8 +4677,8 @@ add_to_history (
    * down, only lines that were added.
    */
   if (histype == HIST_SEARCH && in_map) {
-    if (maptick == last_maptick) {
-      /* Current line is from the same mapping, remove it */
+    if (maptick == last_maptick && hisidx[HIST_SEARCH] >= 0) {
+      // Current line is from the same mapping, remove it
       hisptr = &history[HIST_SEARCH][hisidx[HIST_SEARCH]];
       hist_free_entry(hisptr);
       --hisnum[histype];

src/nvim/version.c

@@ -84,7 +84,7 @@ static int included_patches[] = {
   // 2360,
   // 2359 NA
   // 2358 NA
-  // 2357,
+  2357,
   // 2356,
   2355,
   // 2354,