From: Eli Zaretskii <eliz@gnu.org>
Date: Sat, 16 Jun 2012 09:57:56 +0000 (+0300)
Subject: Fix bug #11653 with cursor positioning in a row that has only strings.
X-Git-Tag: emacs-24.2.90~1199^2~463
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=2f07e6afc932d0be7256c7700e9c11d61075aeaf;p=emacs.git

Fix bug #11653 with cursor positioning in a row that has only strings.

 src/xdisp.c (set_cursor_from_row): Don't dereference glyphs_end.  If
 all the glyphs of the glyph row came from strings, and we have no
 cursor positioning clues, put the cursor on the first glyph of the
 row.
---

diff --git a/src/ChangeLog b/src/ChangeLog
index b5a22a0ebce..3138bea28fa 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,10 @@
+2012-06-16  Eli Zaretskii  <eliz@gnu.org>
+
+	* xdisp.c (set_cursor_from_row): Don't dereference glyphs_end.  If
+	all the glyphs of the glyph row came from strings, and we have no
+	cursor positioning clues, put the cursor on the first glyph of the
+	row.  (Bug#11653)
+
 2012-06-16  Andreas Schwab  <schwab@linux-m68k.org>
 
 	* category.h (CHAR_HAS_CATEGORY): Define as inline.
diff --git a/src/xdisp.c b/src/xdisp.c
index 0eae25de54a..e09116fe0ca 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -14260,6 +14260,7 @@ set_cursor_from_row (struct window *w, struct glyph_row *row,
 	     the cursor is not on this line.  */
 	  if (cursor == NULL
 	      && (row->reversed_p ? glyph <= end : glyph >= end)
+	      && (row->reversed_p ? end > glyphs_end : end < glyphs_end)
 	      && STRINGP (end->object)
 	      && row->continued_p)
 	    return 0;
@@ -14289,6 +14290,21 @@ set_cursor_from_row (struct window *w, struct glyph_row *row,
  compute_x:
   if (cursor != NULL)
     glyph = cursor;
+  else if (glyph == glyphs_end
+	   && pos_before == pos_after
+	   && STRINGP ((row->reversed_p
+			? row->glyphs[TEXT_AREA] + row->used[TEXT_AREA] - 1
+			: row->glyphs[TEXT_AREA])->object))
+    {
+      /* If all the glyphs of this row came from strings, put the
+	 cursor on the first glyph of the row.  This avoids having the
+	 cursor outside of the text area in this very rare and hard
+	 use case.  */
+      glyph =
+	row->reversed_p
+	? row->glyphs[TEXT_AREA] + row->used[TEXT_AREA] - 1
+	: row->glyphs[TEXT_AREA];
+    }
   if (x < 0)
     {
       struct glyph *g;