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Vlastimil Babka wrote: |
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> Peter Gordon wrote: |
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>> On Tue, 2007-07-17 at 19:47 -0400, Mike Frysinger wrote: |
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>>> historically, gcc on x86 has always defaulted to i386. some people noticed |
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>>> recently that glibc-2.6 fails to build in this situation as they were only |
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>>> setting -mtune via CFLAGS, not -march. i'll be tweaking gcc so that it will |
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>>> default -march based on your CHOST. so all the i686-* people will now have a |
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>>> default -march=i686 implied in their gcc systems, i586-* people will |
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>>> have -march=i586, etc... keep in mind this is merely the default. |
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>>> -mike |
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>> Does this mean that any user-set "-march" flag is overridden for these |
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>> cases? Just curious. |
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> |
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> I think he meant CHOST sets just *default* so any user-set -march |
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> overrides that. |
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> But I wonder what happens to user-set -mtune then? Since AFAIK -march |
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> implies -mtune, will also the default -march override user-set -mtune? |
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Previously GCC defaulted to -march=i386, which implied -mtune=i386 |
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(actually, -mcpu for some reason (?)), when neither were set. People |
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are setting CFLAGS="-mtune=pentium4 -O2 -fblah..." which therefore is |
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defaulting to -march=i386 -mtune=pentium4. glibc-2.6 requires >= |
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-march=i486. Kaboom. |
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Now -march=$(echo $CHOST | awk -F- '{ print $1 }'), which implies |
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-mtune=echo $CHOST | awk -F- '{ print $1 }' when neither are set. If |
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_either_ are set by the user, they are overridden. |
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ie. you can still set -march=i386 or -mtune=i386 or whatever you like. |
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-- |
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dirtyepic salesman said this vacuum's guaranteed |
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gentoo org it could suck an ancient virus from the sea |
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9B81 6C9F E791 83BB 3AB3 5B2D E625 A073 8379 37E8 (0x837937E8) |
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