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On Mon, Sep 04, 2017 at 12:39:02PM -0700, Grant wrote |
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> |
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> Now I'm running into "trap invalid opcode" errors on the older |
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> systems. Can I disable some of the newer CPU instruction sets on the |
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> master laptop when compiling to hopefully generate binaries that will |
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> work on the older systems? |
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Yes. You need to find out CPU_FLAGS_X86 and "-march=" values the |
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machines have, and use that in make.conf. Run the commands... |
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cpuinfo2cpuflags-x86 |
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gcc -c -Q -march=native --help=target | grep march= |
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...on the target machines. This will tell you what "native" is and |
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what CPU_FLAGS_X86 values to use. |
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https://gcc.gnu.org/onlinedocs/gcc-6.3.0/gcc/x86-Options.html#x86-Options |
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lists available "march=" options, and what instruction sets they support. |
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E.g. my old core2 desktop shows... |
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[d531][waltdnes][~] cpuinfo2cpuflags-x86 |
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CPU_FLAGS_X86="mmx mmxext sse sse2 sse3 ssse3" |
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[d531][waltdnes][~] gcc -c -Q -march=native --help=target | grep march= |
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-march= core2 |
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Unless the laptops are really old, you can probably get away with... |
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CFLAGS="-O2 march=core2 -mfpmath=sse -fopenmp -fomit-frame-pointer -pipe -fno-unwind-tables -fno-asynchronous-unwind-tables" |
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booby trap 1) Unless all machines are Intel "Atom" family, do *NOT* use |
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a "march=" that implements the "movbe" instruction. |
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booby trap 2) If you throw in any AMD-based machines proceed with care. |
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Can you post the output of... |
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gcc -c -Q -march=native --help=target | grep march= |
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...for all the target machines? |
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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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