2000-12-29 Gerd Moellmann <gerd@gnu.org>
+ * dispnew.c (check_current_matrix_flags) [GLYPH_DEBUG]: New
+ function.
+ (update_window) [GLYPH_DEBUG]: Call it.
+ (scrolling_window): Prevent including current rows which are below
+ what's displayed in the window.
+
+ * xdisp.c (try_window_reusing_current_matrix)
+ <new start <= old start>: Disable rows in the current matrix
+ which are below the window after scrolling.
+
* xdisp.c (move_it_by_lines): Don't do optimizations if NEED_Y_P
is zero. It's not worth the complexity.
(invisible_text_between_p): Put in #if 0 because unused.