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On Thu, Oct 24, 2013 at 09:58:17PM +1100, Adam Carter wrote |
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> I figured that just -march=amdfam10 was a good start, since it implies |
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> MMX, SSE, SSE2, SSE3, SSE4A, 3DNow!, enhanced 3DNow! and ABM, but i |
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> may add the rest of my make.conf CFLAGs since I dont have any issues |
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> with any other software on this system. Is that fair reasoning? |
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Two points... |
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1) Are you cross-compiling, or building on the system that'll be running |
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the kernel? If the build machine will be running the kernel, use |
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"-march=native". It detects what cpu you're running on and builds |
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accordingly. |
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2) Use the flags "-fno-unwind-tables -fno-asynchronous-unwind-tables" to |
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eliminate .eh_frame bloat. See the mailing list archive at |
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http://comments.gmane.org/gmane.linux.busybox/36695 for the gory |
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details. The guys at busybox are anal about code bloat; this is an |
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important issue for them. |
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3) Unless you're debugging, you can get additional size reduction with |
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the "-fomit-frame-pointer" flag. |
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My make.conf has the following CFLAGS line... |
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CFLAGS="-O2 -march=native -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" |
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-- |
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Walter Dnes <waltdnes@××××××××.org> |
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I don't run "desktop environments"; I run useful applications |
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