1 files changed, 57 insertions, 6 deletions

diff --git a/src/w32term.c b/src/w32term.c
index 712bdae5fc3..c37805cb6ca 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -5086,6 +5086,51 @@ w32_read_socket (struct terminal *terminal,
           }
 
         case WM_WINDOWPOSCHANGED:
+          f = x_window_to_frame (dpyinfo, msg.msg.hwnd);
+
+          if (f)
+            {
+              RECT rect;
+              int /* rows, columns, */ width, height, text_width, text_height;
+
+              if (GetClientRect (msg.msg.hwnd, &rect)
+                  /* GetClientRect evidently returns (0, 0, 0, 0) if
+                     called on a minimized frame.  Such "dimensions"
+                     aren't useful anyway.  */
+                  && !(rect.bottom == 0
+                       && rect.top == 0
+                       && rect.left == 0
+                       && rect.right == 0))
+                {
+                  height = rect.bottom - rect.top;
+                  width = rect.right - rect.left;
+                  text_width = FRAME_PIXEL_TO_TEXT_WIDTH (f, width);
+                  text_height = FRAME_PIXEL_TO_TEXT_HEIGHT (f, height);
+                  /* rows = FRAME_PIXEL_HEIGHT_TO_TEXT_LINES (f, height); */
+                  /* columns = FRAME_PIXEL_WIDTH_TO_TEXT_COLS (f, width); */
+
+                  /* TODO: Clip size to the screen dimensions.  */
+
+                  /* Even if the number of character rows and columns
+                     has not changed, the font size may have changed,
+                     so we need to check the pixel dimensions as well.  */
+
+                  if (width != FRAME_PIXEL_WIDTH (f)
+                      || height != FRAME_PIXEL_HEIGHT (f)
+                      || text_width != FRAME_TEXT_WIDTH (f)
+                      || text_height != FRAME_TEXT_HEIGHT (f))
+                    {
+                      change_frame_size (f, text_width, text_height, 0, 1, 0, 1);
+                      SET_FRAME_GARBAGED (f);
+                      cancel_mouse_face (f);
+                      f->win_gravity = NorthWestGravity;
+                    }
+                }
+            }
+
+          check_visibility = 1;
+          break;
+
         case WM_ACTIVATE:
         case WM_ACTIVATEAPP:
           f = x_window_to_frame (dpyinfo, msg.msg.hwnd);
@@ -6052,7 +6097,7 @@ x_calc_absolute_position (struct frame *f)
   int display_top = 0;
   struct frame *p = FRAME_PARENT_FRAME (f);
 
-  if (flags & (XNegative | YNegative))
+  if (!p && flags & (XNegative | YNegative))
     {
       Lisp_Object list;
 
@@ -6078,20 +6123,26 @@ x_calc_absolute_position (struct frame *f)
     }
 
   /* Treat negative positions as relative to the rightmost bottommost
-     position that fits on the screen.  */
+     position that fits on the screen or parent frame.
+
+     I see no need for subtracting 1 from the border widths - is there
+     any on the remaining platforms?  Here these subtractions did put
+     the last pixel line/column of a frame off-display when, for
+     example, a (set-frame-parameter nil 'left '(- 0)) specification was
+     used - martin 20017-05-05. */
   if (flags & XNegative)
     {
       if (p)
         f->left_pos = (FRAME_PIXEL_WIDTH (p)
                        - FRAME_PIXEL_WIDTH (f)
                        + f->left_pos
-                       - (left_right_borders_width - 1));
+                       - left_right_borders_width);
       else
         f->left_pos = (x_display_pixel_width (FRAME_DISPLAY_INFO (f))
                        + display_left
                        - FRAME_PIXEL_WIDTH (f)
                        + f->left_pos
-                       - (left_right_borders_width - 1));
+                       - left_right_borders_width);
     }
 
   if (flags & YNegative)
@@ -6100,13 +6151,13 @@ x_calc_absolute_position (struct frame *f)
         f->top_pos = (FRAME_PIXEL_HEIGHT (p)
                       - FRAME_PIXEL_HEIGHT (f)
                       + f->top_pos
-                      - (top_bottom_borders_height - 1));
+                      - top_bottom_borders_height);
       else
         f->top_pos = (x_display_pixel_height (FRAME_DISPLAY_INFO (f))
                       + display_top
                       - FRAME_PIXEL_HEIGHT (f)
                       + f->top_pos
-                      - (top_bottom_borders_height - 1));
+                      - top_bottom_borders_height);
     }
 
   /* The left_pos and top_pos are now relative to the top and left