patch 9.1.2144: garbage collection may invalidate the recorded buffer changes

Problem:  When garbage collection runs, the list of recorded buffer
	  changes may be incorrectly freed (Sainnhe Park).
Solution: In garbage_collect(), iterate through all buffers and call
          set_ref_in_list() for b_recorded_changes to ensure the list
          and its contents are marked as reachable (Paul Ollis).

fixes:  #19300
closes: #19375

Signed-off-by: Paul Ollis <paul@cleversheep.org>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/doc/version9.txt

@@ -52542,4 +52542,11 @@ Problem:  When a popup window partially overlaps a wide character
 Solution: When a wide character is partially blocked by a popup, clear both
           cells in the screen buffer to prevent garbage (Yasuhiro Matsumoto).
 
+Patch 9.1.2144
+Problem:  When garbage collection runs, the list of recorded buffer
+	  changes may be incorrectly freed (Sainnhe Park). 
+Solution: In garbage_collect(), iterate through all buffers and call
+          set_ref_in_list() for b_recorded_changes to ensure the list
+          and its contents are marked as reachable (Paul Ollis).
+
  vim:tw=78:ts=8:noet:ft=help:norl:fdm=manual:nofoldenable

src/gc.c

@@ -121,8 +121,11 @@ garbage_collect(int testing)
 
     // buffer-local variables
     FOR_ALL_BUFFERS(buf)
+    {
 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
 							NULL, NULL, NULL);
+	abort = abort || set_ref_in_list(buf->b_recorded_changes, copyID);
+    }
 
     // window-local variables
     FOR_ALL_TAB_WINDOWS(tp, wp)

src/version.c

@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2144,
 /**/
     2143,
 /**/