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On Tue, 29 May 2012 22:56:07 +0200 |
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Rafa Griman <rafagriman@×××××.com> wrote: |
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> Hi Vaeth :) |
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> |
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> On Tue, May 29, 2012 at 7:02 PM, Vaeth |
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> <vaeth@××××××××××××××××××××××××.de> wrote: |
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> > On Tue, 29 May 2012, Rafa Griman wrote: |
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> >> |
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> >> gawk: cmd. line:3: error: Unmatched [ or [^: /[^[:space:]]/ |
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> > |
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> > |
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> > Your gawk is broken. This happens if you emerged gawk with |
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> > current gcc and aggressive FLAGS like -DNDEBUG or -flto. |
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> > Not sure whether it is a bug of gawk or gcc. |
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> |
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> |
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> So it seems to be the CFLAGS :( As I said in my previous e-mail, I was |
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> "experimenting" a bit with them ... I'll be more conservative ;) |
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Well, on the one hand the flags don;t seem to be too bad overall, but |
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on the other hand there's the golden rule of Gentoo: |
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Don't stuff around with CFLAGS |
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Why not? Well, there's the ricer phenomenon where changed CFLAGS |
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worsen performance and stability but the user's own bias convinces |
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him/her that it's actually vastly improved. |
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|
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Some tweaks are perfectly OK, like the multimedia and cpu-specific |
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stuff (sse, mmx and all their related cousins). These are normally safe |
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and can give huge gains with video playback. Likewise for the GPU tweaks |
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once those hit mainline usage. |
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One last tweak, if the code is built on the machine that will run it |
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(the usual case, replace -march and -mtune with just "-march=native". |
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It has exactly the same effect but is easier to read, is |
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self-documenting and allows the compiler to attempt it's best (the |
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compiler usually does know much better what to do than you do) |
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|
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-- |
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Alan McKinnnon |
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alan.mckinnon@×××××.com |
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