[FFmpeg-devel] [PATCH] mipsen require compilation with -DPIC since gcc-4.3

Måns Rullgård mans
Sun Sep 21 17:50:51 CEST 2008


Luca Barbato <lu_zero at gentoo.org> writes:

> M?ns Rullg?rd wrote:
>> Those are clearly compiler/linker bugs.
>
> Discuss with the ABI authors...

If it used to work, and now has stopped working, there has to be a bug
somewhere.  Since FFmpeg didn't change, the bug must be in gcc.

>> In general, we avoid bug
>> workarounds that have a negative performance impact, and PIC code
>> certainly is slower than non-PIC on MIPS, at least when using gcc.
>
> Given the number of registers mips has, I'm not so sure, Reinhard could 
> you please provide a benchmark?

I'm talking about the extra indirection imposed by PIC.

> If it does not impact performance (loadtime should be improved, runtime 
> could be impaired) I think won't be a problem applying it.

There is no reason for MIPS to not support textrels in shared libs.
The mention of gcc 4.3 suggests that gcc has started doing something
stupid, which should be reported as a bug.

-- 
M?ns Rullg?rd
mans at mansr.com




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