Windows: Added missing NULL check after SDL_stack_alloc().
SDL_stack_alloc() might wrap SDL_malloc() which can return NULL.
--- a/src/video/windows/SDL_windowsframebuffer.c Sun Dec 06 17:50:51 2015 +0100
+++ b/src/video/windows/SDL_windowsframebuffer.c Sun Dec 06 17:51:11 2015 +0100
@@ -42,6 +42,9 @@
/* Find out the format of the screen */
size = sizeof(BITMAPINFOHEADER) + 256 * sizeof (RGBQUAD);
info = (LPBITMAPINFO)SDL_stack_alloc(Uint8, size);
+ if (!info) {
+ return SDL_OutOfMemory();
+ }
SDL_memset(info, 0, size);
info->bmiHeader.biSize = sizeof(BITMAPINFOHEADER);