dnl Introduce --enable-native-optimizations command line argument to turn on
dnl -march=native compiler flag, disabled by default.
dnl
AC_ARG_ENABLE(
[native-optimizations],
[AS_HELP_STRING([--enable-native-optimizations], [Enable non-portable optimizations for your own CPU by compiling with -march=native @<:@default=no@:>@])]