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

[Diego Biurrun]

On Mon, Sep 22, 2008 at 10:19:47AM +0200, Reinhard Tartler wrote:
> M?ns Rullg?rd <mans at mansr.com> writes:
> 
> > Mentioning this in the original email would have spared us this
> > discussion.  Do you have a reference for that?
> 
> Quoting from http://gcc.gnu.org/gcc-4.3/changes.html
> 
> MIPS
> Changes to existing configurations
> 
>     [...]
>     * GNU/Linux configurations now generate -mno-shared code unless
>       overridden by -fpic, -fPIC, -fpie or -fPIE.
>     [...]
> 
> You can verify Thiemo as Linux/MIPS gcc upstream developer by checking
> your gcc changelog.
> 
> Btw, MIPS has only very recently added non-PIC executable
> support. c.f. http://www.linux-mips.org/archives/linux-mips/2008-06/msg00280.html
> 
> In short, there is no performance penalty with adding this switch at
> all. GCC 4.3 brings some performance when linking ffmpeg statically, but
> breaks when compiled at shared libs now.  ths told me in private query
> that the fact that it did not fail was sheer luck. The fact that it ld
> doesn't fail can be considered as a bug.
> 
> What else references do you need for this single one-liner?!

What would be a good commit message for this?  My current draft is:

Add MIPS to list of architectures requiring PIC flags.
gcc used to do this automatically because non-PIC builds were not
supported.  Starting with gcc 4.3 non-PIC static builds are
supported and the flag has to be passed explicitly.

Diego