[FFmpeg-devel] Question about -fPIC usage for some files

Loren Merritt lorenm
Sat Feb 9 07:12:31 CET 2008

On Fri, 8 Feb 2008, Trent Piepho wrote:
> Since version 3 something, gcc can use other registers besides ebx, and
> might not use ebx at all if the function doesn't do anything that requires
> access to the pic pointer.  If a function accesses no globals, does not
> take the address of a fuction, or call a function in another shared
> library, it shouldn't need to load the pic register.

Yes, but that only affects compilation of C. As of gcc-4.2.2, even if 
there is no need for a PIC register, it still refuses to allocate any asm 
arguments to ebx.

--Loren Merritt

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