Fix bug#71929

* src/image.c (free_image_cache): Unconditionally release image
cache, as this function is only called with its existence
already established.

* src/xfaces.c (free_frame_faces): Clear FRAME_IMAGE_CACHE (f).
(bug#71929)

3 files changed, 14 insertions, 14 deletions

diff --git a/src/dispextern.h b/src/dispextern.h
index 51dc354d37c..cc248a4472e 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -3653,7 +3653,7 @@ extern void x_kill_gs_process (Pixmap, struct frame *);
 extern Lisp_Object image_find_image_file (Lisp_Object);
 
 struct image_cache *make_image_cache (void);
-void free_image_cache (struct frame *);
+extern void free_image_cache (struct frame *);
 void clear_image_caches (Lisp_Object);
 void mark_image_cache (struct image_cache *);
 void image_prune_animation_caches (bool);
diff --git a/src/image.c b/src/image.c
index 2945447b962..2ee2f3245be 100644
--- a/src/image.c
+++ b/src/image.c
@@ -2304,23 +2304,18 @@ void
 free_image_cache (struct frame *f)
 {
   struct image_cache *c = FRAME_IMAGE_CACHE (f);
-  if (c)
-    {
-      ptrdiff_t i;
+  ptrdiff_t i;
 
-      /* Cache should not be referenced by any frame when freed.  */
-      eassert (c->refcount == 0);
+  /* Cache should not be referenced by any frame when freed.  */
+  eassert (c->refcount == 0);
 
-      for (i = 0; i < c->used; ++i)
-        free_image (f, c->images[i]);
-      xfree (c->images);
-      xfree (c->buckets);
-      xfree (c);
-      FRAME_IMAGE_CACHE (f) = NULL;
-    }
+  for (i = 0; i < c->used; ++i)
+    free_image (f, c->images[i]);
+  xfree (c->images);
+  xfree (c->buckets);
+  xfree (c);
 }
 
-
 /* Clear image cache of frame F.  FILTER=t means free all images.
    FILTER=nil means clear only images that haven't been
    displayed for some time.
diff --git a/src/xfaces.c b/src/xfaces.c
index 188dd4778bc..684b6ccfac7 100644
--- a/src/xfaces.c
+++ b/src/xfaces.c
@@ -712,6 +712,11 @@ free_frame_faces (struct frame *f)
           --image_cache->refcount;
           if (image_cache->refcount == 0)
             free_image_cache (f);
+
+          /* The `image_cache' field must be emptied, in case references
+             to this dead frame should remain and be scanned by GC.
+             (bug#71929) */
+          FRAME_IMAGE_CACHE (f) = NULL;
         }
     }
 #endif /* HAVE_WINDOW_SYSTEM */