altmark(a)de.ibm.com writes: Does my patch I posted in a separate thread help? Index: redisplay.c =================================================================== RCS file: /usr/CVSroot/XEmacs/xemacs/src/redisplay.c,v retrieving revision 1.55.2.41 diff -u -u -r1.55.2.41 redisplay.c --- redisplay.c 2000/02/17 14:16:46 1.55.2.41 +++ redisplay.c 2000/02/24 17:48:24 ＠＠ -5157,6 +5157,9 ＠＠ else prop = 0; + /* Make sure this is set always */ + /* Note the conversion at end */ + w->window_end_pos[type] = start_pos; while (ypos < yend) { struct display_line dl; ＠＠ -5260,10 +5263,14 ＠＠ Dynarr_free (prop); /* #### More not quite right, but close enough. */ - /* #### Ben sez: apparently window_end_pos[] is measured + /* Ben sez: apparently window_end_pos[] is measured as the number of characters between the window end and the end of the buffer? This seems rather weirdo. What's - the justification for this? */ + the justification for this? + + JV sez: Because BUF_Z (b) would be a good initial value, however + that can change. This representation allows initalizing with 0. + */ w->window_end_pos[type] = BUF_Z (b) - w->window_end_pos[type]; if (need_modeline) ＠＠ -7553,11 +7560,20 ＠＠ displayed. The end of the last line is also know as the window end position. + WARNING: Under some circumstances it is possible that rediplay failed + to layout any lines for the windows. In that case this function returns + 0 as an error condition when may_error is non-zero and a normalized + value of startp otherwise. + Under normal circumstances this is rare. However it seems that it seems + that in can occur when computing the window a mouse event occured in and + the code their can handle the 0 error condition. + #### With a little work this could probably be reworked as just a call to start_with_line_at_pixpos. */ static Bufpos -start_end_of_last_line (struct window *w, Bufpos startp, int end) +start_end_of_last_line (struct window *w, Bufpos startp, int end, + int may_error) { struct buffer *b = XBUFFER (w->buffer); line_start_cache_dynarr *cache = w->line_start_cache; ＠＠ -7577,8 +7593,11 ＠＠ start_elt = point_in_line_start_cache (w, cur_start, 0); if (start_elt == -1) - abort (); /* this had better never happen */ - + { + stderr_out ("Soft assert triggered (start_end_of_last_line)\n"); + return may_error ? 0 : startp; + } + while (1) { int height = Dynarr_atp (cache, start_elt)->height; ＠＠ -7641,7 +7660,7 ＠＠ Bufpos start_of_last_line (struct window *w, Bufpos startp) { - return start_end_of_last_line (w, startp, 0); + return start_end_of_last_line (w, startp, 0 , 0); } /* For the given window W, if display starts at STARTP, what will be ＠＠ -7651,9 +7670,16 ＠＠ Bufpos end_of_last_line (struct window *w, Bufpos startp) { - return start_end_of_last_line (w, startp, 1); + return start_end_of_last_line (w, startp, 1, 0); } +static Bufpos +end_of_last_line_may_error (struct window *w, Bufpos startp) +{ + return start_end_of_last_line (w, startp, 1, 1); +} + + /* For window W, what does the starting position have to be so that the line containing POINT will cover pixel position PIXPOS. */ ＠＠ -8807,7 +8833,7 ＠＠ if (!MARKERP ((*w)->start[CURRENT_DISP])) *closest = 0; else - *closest = end_of_last_line (*w, + *closest = end_of_last_line_may_error (*w, marker_position ((*w)->start[CURRENT_DISP])); *col = 0; UPDATE_CACHE_RETURN;