[Ffmpeg-devel] [BUG] Compilation failure when using --disable-opts

Panagiotis Issaris takis.issaris
Wed Mar 14 13:58:20 CET 2007


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi,

Reimar D?ffinger schreef:
> Hello,
> [...]
> On Thu, Mar 08, 2007 at 10:42:34PM +0100, Michael Niedermayer wrote:
>> On Thu, Mar 08, 2007 at 09:46:33PM +0100, Panagiotis Issaris wrote:
>>> With -O0 or without -Ox flag (which is what is used when --enable-opts
>>> is passed to configure) the testapp compiles fine in either case.
>>>
>>> So, with the flags used for the compilation of cabac.c, the testapp
>>> compiles fine.
>> compiles yes, works no
>>
>> try
>> int main() {
>>     volatile int i=0;
>>     asm volatile (
>>         "xorl %%ebp, %%ebp"
>>     ::: "%ebp");
>>     return i;
>> }
>>
>> this will crash with -O0 and without -fomit-frame-pointer
> 
> Isn't the (semi-) official gcc statement still that -O0 is and always
> will be broken?
That would be horrible... Have you got a link to some GCC source stating so?

> Was some time ago, but IIRC on SPARC it would miscompile even
> some ordinary C code involving syscalls...
I noticed more problems (wrongly generated code) with GCC on non-x86
architectures too, but x86 always seem to work quite okay...

With friendly regards,
Takis
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iD8DBQFF9/Fr9kOxLuzz4CkRAnXAAJ9vf6VjUaYnm3AboS9KRYwtkzQ06ACeOkmc
0haYZKvNLrn2PKHo5ar8mtg=
=nCvi
-----END PGP SIGNATURE-----




More information about the ffmpeg-devel mailing list