Fix bug #13937 with creating a maximized frame on MS-Windows.

 src/w32term.c (w32_read_socket): If we Emacs frame is being
 activated, call w32fullscreen_hook, to make sure the new frame
 dimensions are in effect.

1 files changed, 11 insertions, 1 deletions

diff --git a/src/w32term.c b/src/w32term.c
index 6137d54c837..680ad668ab3 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -236,6 +236,7 @@ static void my_set_focus (struct frame *, HWND);
 #endif
 static void my_set_foreground_window (HWND);
 static void my_destroy_window (struct frame *, HWND);
+static void w32fullscreen_hook (FRAME_PTR);
 
 #ifdef GLYPH_DEBUG
 static void x_check_font (struct frame *, struct font *);
@@ -4717,7 +4718,16 @@ w32_read_socket (struct terminal *terminal,
         case WM_ACTIVATEAPP:
           f = x_window_to_frame (dpyinfo, msg.msg.hwnd);
           if (f)
-            x_check_fullscreen (f);
+            {
+              /* If we are being activated, run the full-screen hook
+                 function, to actually install the required size in
+                 effect.  This is because when the hook is run from
+                 x_set_fullscreen, the frame might not yet be visible,
+                 if that call is a result of make-frame.  */
+              if (msg.msg.wParam)
+                w32fullscreen_hook (f);
+              x_check_fullscreen (f);
+            }
           check_visibility = 1;
           break;