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On 04/30/2010 03:09 PM, David W Noon wrote: |
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> On Fri, 30 Apr 2010 12:10:02 +0200, Roger Mason wrote about |
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> [gentoo-user] Compiling 32 bit library on x86_64: |
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> |
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>> Hello, |
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>> |
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>> I need to compile a 32 bit version of libtermcap on an x86_64 |
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>> (multilib) system. Can someone tell me how to set up CFLAGS? This is |
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>> what I have at the moment: |
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>> |
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>> CFLAGS="-O2 -m32 -march=native -msse3 -pipe" |
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>> CXXFLAGS="-O2 -m32 -march=native -msse3 -pipe" |
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> |
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> The -march=native will shoot you in the foot. Pick a 32-bit |
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> architecture and use that instead; e.g. -march=i686 |
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> |
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> Then, -msse3 could also be problematic, unless the target is a very late |
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> model Pentium 4. I would ditch that too. |
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None of those options are problematic. -march=native has nothing to do |
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with 32/64 bit. Every 64-bit CPU is 32-bit compatible and has zero |
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consequence. |
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I think you fell into the logical trap that 32-bit CPUs are not 64-bit |
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compatible but it's OK vice versa :) Meaning you can't use "-m64 |
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-march=i686". But you *can* and *should* use "-m32 -march=core2". |
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