Zebediah Figura : user32/tests: Work around a failure on Windows < Vista.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 6e4d441ce11739b145dae200d7b20743c64147de
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=6e4d441ce11739b145dae200d7b20743c64147de

Author: Zebediah Figura <z.figura12 at gmail.com>
Date:   Wed Jan  1 12:14:13 2020 -0600

user32/tests: Work around a failure on Windows < Vista.

Signed-off-by: Zebediah Figura <z.figura12 at gmail.com>
Signed-off-by: Alexandre Julliard <julliard at winehq.org>

---

 dlls/user32/tests/winstation.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/dlls/user32/tests/winstation.c b/dlls/user32/tests/winstation.c
index aaa51d560a..4aa5565b96 100644
--- a/dlls/user32/tests/winstation.c
+++ b/dlls/user32/tests/winstation.c
@@ -51,7 +51,12 @@ static void register_class(void)
     WNDCLASSA cls;
 
     cls.style = CS_DBLCLKS;
-    cls.lpfnWndProc = DefWindowProcA;
+    /* Windows < Vista apparently checks lpfnWndProc against the address of
+     * DefWindowProcA(), and for some reason fails to change the thread desktop
+     * after creating and destroying a window if it doesn't match. Using an IAT
+     * (as is default) or a wrapper triggers this, so use GetProcAddress() as
+     * a workaround. */
+    cls.lpfnWndProc = (void *)GetProcAddress(GetModuleHandleA("user32"), "DefWindowProcA");
     cls.cbClsExtra = 0;
     cls.cbWndExtra = 0;
     cls.hInstance = GetModuleHandleA(0);