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Bug 1278 - Crash in SDL_UnlockYUVOverlay with smpeg
Summary: Crash in SDL_UnlockYUVOverlay with smpeg
Status: RESOLVED FIXED
Alias: None
Product: SDL
Classification: Unclassified
Component: video (show other bugs)
Version: 1.2.14
Hardware: x86 Linux
: P2 major
Assignee: Sam Lantinga
QA Contact: Sam Lantinga
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2011-08-16 01:59 UTC by Anton Yarth
Modified: 2011-09-13 11:50 UTC (History)
2 users (show)

See Also:

Attachments
App for demonstration of bug (549.86 KB, application/x-gzip)
2011-08-21 19:28 UTC, Anton Yarth 		Details
View All Add an attachment (proposed patch, testcase, etc.)

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Description Anton Yarth 2011-08-16 01:59:16 UTC 
After sdl update in my distro from version from 2009 year to current(update from 12 august 2011) appears bugs with smpeg.
Video-files with resolution 320x168(and other) plays like that:
http://img221.imageshack.us/img221/9692/bugkf.jpg
but must be:
http://img62.imageshack.us/img62/5854/goodlu.jpg

And in sometimes with other video-files project crashes with this callstack:
http://img402.imageshack.us/img402/5536/callstack.png
(Sometimes this window shows 0x00008800 instead of SDL_UnlockYUVOverlay)
Comment 1 Anton Yarth 2011-08-16 02:09:46 UTC 
On files with resolution 320x172 all looks OK
Comment 2 Anton Yarth 2011-08-17 19:40:33 UTC 
Oh, i found bug. This bug steel presents while SDL_ASSEMBLY_ROUTINES is defined. Turning it off gives no errors and crashes. I think it's gcc 4.6.1 optimization problem.
Comment 3 Anton Yarth 2011-08-17 19:47:44 UTC 
hmm, peoples from tests code and answer what sdl use not correct asm code, that cause errors(such as no compilation on gcc 4.6.1 with -O0 flag), and that regression.
Comment 4 Anton Yarth 2011-08-21 19:28:40 UTC 
Created attachment 678 [details]
App for demonstration of bug
Comment 5 Anton Yarth 2011-08-21 19:37:38 UTC 
With gcc 4.6.1 sdl-code cause this bug until comment #define SDL_ASSEMBLY_ROUTINES 1", and with -O0 optimization it give wrong mmx code.
This bug, marked as "bug of sdl" on gcc http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50111
And this bug marked as "bug of sdl" on Archlinux https://bugs.archlinux.org/task/25634
Comment 6 Sam Lantinga 2011-09-06 19:49:17 UTC 
This is fixed in Mercurial:
http://hg.libsdl.org/SDL/rev/819e85555d4d

Thanks!
Comment 7 Anton Yarth 2011-09-06 23:31:11 UTC 
No appears:
./src/video/SDL_RLEaccel.c: In function ‘SDL_RLEBlit’:
./src/video/SDL_RLEaccel.c:831:5: error: impossible constraint in ‘asm’
.... /*many lines*/
./src/video/SDL_RLEaccel.c:831:5: error: impossible constraint in ‘asm’
./src/video/SDL_RLEaccel.c:930:6: error: impossible constraint in ‘asm’
..../*many lines*/
./src/video/SDL_RLEaccel.c:930:6: error: impossible constraint in ‘asm’
Comment 8 Ryan C. Gordon 2011-09-12 11:18:13 UTC 
This bug is happening on Haiku, too:


   http://buildbot.libsdl.org/builders/sdl-haiku/builds/21/steps/compile/logs/stdio


--ryan.
Comment 9 Ryan C. Gordon 2011-09-12 11:19:11 UTC 
(In reply to comment #8)
> This bug is happening on Haiku, too:

Specifically: the "impossible constraint" error, I mean.

Should we just disable the MMX code across the board?

--ryan.
Comment 10 Anton Yarth 2011-09-12 17:51:08 UTC 
(In reply to comment #9)
> (In reply to comment #8)
> > This bug is happening on Haiku, too:
> 
> Specifically: the "impossible constraint" error, I mean.
> 
> Should we just disable the MMX code across the board?
> 
> --ryan.

By your patch in mercurial (http://hg.libsdl.org/SDL/rev/739ad55fe50d) not disabled all mmx-code, SDL_yuv_sw.c and SDL_yuv_mmx.c still cause not correct drawning or crashes, because they have mmx-instructions too.
Comment 11 Anton Yarth 2011-09-12 18:00:10 UTC 
And if i try build sdl-1.2 from current(2011-09-13  07:58) mercurial with CFLAGS="-O0 -g" it's now stops on:
./src/video/SDL_blit_A.c: In function ‘BlitRGBtoRGBSurfaceAlpha128MMX’:
./src/video/SDL_blit_A.c:247:3: error: impossible constraint in ‘asm’
./src/video/SDL_blit_A.c:247:3: error: impossible constraint in ‘asm’
make: *** [build/SDL_blit_A.lo] Error 1

I think we must disable mmx code in all files with blitting.
Comment 12 Ryan C. Gordon 2011-09-13 11:01:43 UTC 
(In reply to comment #10)
> By your patch in mercurial (http://hg.libsdl.org/SDL/rev/739ad55fe50d) not
> disabled all mmx-code, SDL_yuv_sw.c and SDL_yuv_mmx.c still cause not correct
> drawning or crashes, because they have mmx-instructions too.

I wasn't trying to disable this code with that patch.

--ryan.
Comment 13 Ryan C. Gordon 2011-09-13 11:50:43 UTC 
Screw it, I turned off the rest of the MMX code.

Fixed in hg changeset 867c4c3604b7.

--ryan.