2 files changed, 6 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index cfb151d0f99..e001f967382 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,8 @@
 2001-12-18  Pavel Jan,Bm(Bk  <Pavel@Janik.cz>
 
+        * xdisp.c (window_box_height): Do not return negative values.
+        From Gerd Moellmann <gerd@gnu.org>.
+
         * keyboard.c (head_table): Add missing braces around initializer.
 
         * term.c (keys): Likewise.
diff --git a/src/xdisp.c b/src/xdisp.c
index b2a5a1d08a5..1dd5f0fa985 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -910,7 +910,9 @@ window_box_height (w)
         height -= estimate_mode_line_height (f, HEADER_LINE_FACE_ID);
     }
 
-  return height;
+  /* With a very small font and a mode-line that's taller than
+     default, we might end up with a negative height.  */
+  return max (0, height);
 }