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Re: -fpic no optimization...


> I was compiling LZMA SDK (http://www.7-zip.org/, LzmaDecode.c) and just
> for curiosity I looked at output assembler. I noted that when PIC is
> enabled (-fpic, Linux Intel) ebx is reserved to global pointer. However
> LzmaDecode do not access any global data and do not call other functions
> (no relocations at all) so why not use ebx register? -fpic make compiler
> just not use ebx. I tried using different versions (gcc 3.4.4 from
> Fedora Core 3 and 4.0.2 from Fedora Core 4) with same result.
> 

I just tried same test with gcc 4.2.0 20051231 with same behavior.

Frediano Ziglio




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