Fix bug #11367 with assertion violation during vertical motion in egg.el.

src/xdisp.c (pos_visible_p): If already at a newline from the
 display string before the 'while' loop, don't walk back the glyphs
 from it3.glyph_row.  Solves assertion violation when the display
 string begins with a newline (egg.el).
This commit is contained in:
Eli Zaretskii 2012-04-29 20:19:08 +03:00
parent 5a5fd9f33a
commit 2fa85638a0
2 changed files with 20 additions and 1 deletions

View file

@ -1,3 +1,10 @@
2012-04-29 Eli Zaretskii <eliz@gnu.org>
* xdisp.c (pos_visible_p): If already at a newline from the
display string before the 'while' loop, don't walk back the glyphs
from it3.glyph_row. Solves assertion violation when the display
string begins with a newline (egg.el). (Bug#11367)
2012-04-24 Chong Yidong <cyd@gnu.org>
* xselect.c (x_convert_selection): Initialize a pointer (Bug#11315).

View file

@ -1375,6 +1375,7 @@ pos_visible_p (struct window *w, EMACS_INT charpos, int *x, int *y,
Lisp_Object startpos, endpos;
EMACS_INT start, end;
struct it it3;
int it3_moved;
/* Find the first and the last buffer positions
covered by the display string. */
@ -1431,6 +1432,15 @@ pos_visible_p (struct window *w, EMACS_INT charpos, int *x, int *y,
begins. */
start_display (&it3, w, top);
move_it_to (&it3, -1, 0, top_y, -1, MOVE_TO_X | MOVE_TO_Y);
/* If it3_moved stays zero after the 'while' loop
below, that means we already were at a newline
before the loop (e.g., the display string begins
with a newline), so we don't need to (and cannot)
inspect the glyphs of it3.glyph_row, because
PRODUCE_GLYPHS will not produce anything for a
newline, and thus it3.glyph_row stays at its
stale content it got at top of the window. */
it3_moved = 0;
/* Finally, advance the iterator until we hit the
first display element whose character position is
CHARPOS, or until the first newline from the
@ -1442,6 +1452,7 @@ pos_visible_p (struct window *w, EMACS_INT charpos, int *x, int *y,
if (IT_CHARPOS (it3) == charpos
|| ITERATOR_AT_END_OF_LINE_P (&it3))
break;
it3_moved = 1;
set_iterator_to_next (&it3, 0);
}
top_x = it3.current_x - it3.pixel_width;
@ -1452,7 +1463,8 @@ pos_visible_p (struct window *w, EMACS_INT charpos, int *x, int *y,
display string, move back over the glyphs
produced from the string, until we find the
rightmost glyph not from the string. */
if (IT_CHARPOS (it3) != charpos && EQ (it3.object, string))
if (it3_moved
&& IT_CHARPOS (it3) != charpos && EQ (it3.object, string))
{
struct glyph *g = it3.glyph_row->glyphs[TEXT_AREA]
+ it3.glyph_row->used[TEXT_AREA];