From dec971d685d77a1ca97d77e49cc60c2634d480bc Mon Sep 17 00:00:00 2001 From: "Ryan C. Gordon" Date: Mon, 4 Feb 2008 17:22:56 +0000 Subject: [PATCH] Date: Sat, 2 Feb 2008 22:08:05 +0100 From: Marcus von Appen To: sdl@lists.libsdl.org Subject: [SDL] [Patch] SDL-1.2 SDL_revcpy() asm patch for the cld flag Hi, as reported through the FreeBSD bug tracking system in SDL 1.2.13 (and in the 1.2 branch, if I see that correctly) the SDL_revcpy() macro sets the direction flag (std), but does not clear it afterwards (cld), which is wrong according to the GCC and SYS V specs. This can cause some weird side effects, which in turn can lead to memory corruption. You can read the full report with a detailed description and test program at http://www.freebsd.org/cgi/query-pr.cgi?pr=ports/120052 Attached is the submitted patch, which fixes the issue. Regards Marcus --HG-- branch : SDL-1.2 extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%402713 --- include/SDL_stdinc.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/SDL_stdinc.h b/include/SDL_stdinc.h index e47c21daf..e74829708 100644 --- a/include/SDL_stdinc.h +++ b/include/SDL_stdinc.h @@ -331,6 +331,7 @@ do { \ __asm__ __volatile__ ( \ "std\n\t" \ "rep ; movsl\n\t" \ + "cld\n\t" \ : "=&c" (u0), "=&D" (u1), "=&S" (u2) \ : "0" (n >> 2), \ "1" (dstp+(n-4)), "2" (srcp+(n-4)) \