On 2016.09.18 at 11:02 +0000, Mahmood Naderan wrote: > > That switch caught my eye because its the opposite of -mach=native > > Actually I didn't understand. Do you mean that -march=x86-64 is an invalid option? No, it is the default. But he's right that the options is undocumented. % echo "" | g++ -c -x c++ -v - 2>&1 | grep march COLLECT_GCC_OPTIONS='-c' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64' /usr/libexec/gcc/x86_64-pc-linux-gnu/6.2.1/cc1plus -quiet -v -D_GNU_SOURCE - -quiet -dumpbase - -mtune=generic -march=x86-64 -auxbase - -version -o /tmp/ccZLSzYL.s COLLECT_GCC_OPTIONS='-c' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64' COLLECT_GCC_OPTIONS='-c' '-v' '-shared-libgcc' '-mtune=generic' '-march=x86-64' -- Markus
