flac dev - Mar 2014 - PATCH: OS SSE support detection for GCC on Windows

libFLAC for Windows compiled with GCC/MinGW can't detect SSE OS support:
it can't use GCC+Linux detection code and can't use MSVC+Win32 code that
uses SEH (__try/__except). So it doesn't use any SSE/SSE2/etc routines.

One way to fix it is to call configure script with --enable-sse
(flac will probably crash on Win95/WinNT4 but who cares).

Another way is to add a new code just for GCC+Win32 case.
The patch is attached.



...One thing that worries me is the comment in cpu.c:
     /* sigill_handler flavor resulted in several crash reports on win32 */
but the corresponding ticket #307 ( http://sourceforge.net/p/flac/bugs/307/ )
doesn't reveal any details.
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Le 09/03/2014 22:26, lvqcl a ?crit :
> libFLAC for Windows compiled with GCC/MinGW can't detect SSE OS
support:
> it can't use GCC+Linux detection code and can't use MSVC+Win32 code
that
> uses SEH (__try/__except). So it doesn't use any SSE/SSE2/etc routines.
>
> One way to fix it is to call configure script with --enable-sse
> (flac will probably crash on Win95/WinNT4 but who cares).
>
> Another way is to add a new code just for GCC+Win32 case.
> The patch is attached.
I may say something stupid but is this helpful ?

http://stackoverflow.com/questions/6121792/how-to-check-if-a-cpu-supports-the-sse3-instruction-set

-- 
Olivier TRISTAN
uvi.net

op 11-03-14 15:57, Olivier Tristan schreef:
> I may say something stupid but is this helpful ? 
>
http://stackoverflow.com/questions/6121792/how-to-check-if-a-cpu-supports-the-sse3-instruction-set

That question on stackoverflow is about CPU support, the patch 
you replied to was about OS support. Because of the registers 
used (which must be saved and restored on a context switch), the 
OS must support a certain instruction set or the program will 
crash. AFAIK the detection of those things is unrelated.

op 09-03-14 22:26, lvqcl schreef:
> One way to fix it is to call configure script with --enable-sse
> (flac will probably crash on Win95/WinNT4 but who cares).
FLAC already wasn't working on Windows 98 and older because of 
the UTF-8 implementation that was merged for flac 1.3.0, so no 
one will care I guess.