Fix bug#69140

* src/window.c (grow_mini_window): Don't adjust frame matrices
or force redisplay if the provided window cannot be
resized.  (bug#69140)

1 files changed, 8 insertions, 1 deletions

diff --git a/src/window.c b/src/window.c
index 565ad00804f..0c84b4f4bf3 100644
--- a/src/window.c
+++ b/src/window.c
@@ -5380,7 +5380,14 @@ grow_mini_window (struct window *w, int delta)
       grow = call3 (Qwindow__resize_root_window_vertically,
                     root, make_fixnum (- delta), Qt);
 
-      if (FIXNUMP (grow) && window_resize_check (r, false))
+      if (FIXNUMP (grow)
+          /* It might be impossible to resize the window, in which case
+             calling resize_mini_window_apply will set off an infinite
+             loop where the redisplay cycle so forced returns to
+             resize_mini_window, making endless attempts to expand the
+             minibuffer window to this impossible size.  (bug#69140) */
+          && XFIXNUM (grow) != 0
+          && window_resize_check (r, false))
         resize_mini_window_apply (w, -XFIXNUM (grow));
     }
 }