Fix Bug#16284.

* dispnew.c (change_frame_size_1): Take old width of root window
from that window's pixel width.  Bug#16284.

2 files changed, 6 insertions, 2 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index e1e9777fa4f..fd2b6db1165 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2013-12-30  Martin Rudalics  <rudalics@gmx.at>
+
+        * dispnew.c (change_frame_size_1): Take old width of root window
+        from that window's pixel width.  Bug#16284.
+
 2013-12-29  Paul Eggert  <eggert@cs.ucla.edu>
 
         Plain copy-file no longer chmods an existing destination (Bug#16133).
diff --git a/src/dispnew.c b/src/dispnew.c
index cbf1963feca..5ba07afe09d 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -5463,8 +5463,7 @@ change_frame_size_1 (struct frame *f, int new_width, int new_height,
                      bool pretend, bool delay, bool safe, bool pixelwise)
 {
   int new_text_width, new_text_height, new_root_width;
-  int old_root_width = (FRAME_PIXEL_WIDTH (f)
-                        - 2 * FRAME_INTERNAL_BORDER_WIDTH (f));
+  int old_root_width = WINDOW_PIXEL_WIDTH (XWINDOW (FRAME_ROOT_WINDOW (f)));
   int new_cols, new_lines;
   ptrdiff_t count = SPECPDL_INDEX ();