[FFmpeg-devel] [PATCH] Fix compilation with llvm-gcc on x86_64

Loren Merritt lorenm
Sun Nov 1 19:26:28 CET 2009

On Sun, 1 Nov 2009, Mans Rullgard wrote:

> LLVM requires matching input and output asm parameters to have the
> same type.  For the FASTDIV macro, an (int) cast on the input fixes
> this trivially.
> Apparently, LLVM also dislikes +g constraints with int operands on
> x86_64, probably due to register being wider than int.  Using a +r
> constraint instead works with gcc 3.4.6, gcc 4.3.4, and llvm-gcc 2.6.

But register isn't wider than int. "+g" associated with a 32bit variable 
means "either a 32bit register or a 32bit memory", and likewise for other 

--Loren Merritt

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