Nathanael Nerode writes: > Matthias Klose wrote: > >so make -mcpu=i586 -mtune=i686 the default? anything else as the > >default? > > Just to clarify, that would be the default for *hurd* only, right?
yes > There's no good reason to drop 486 support under Linux. So for Linux, > it would be -mcpu=i486 -mtune-i686 as the default, correct? yes, except gcc-3.3 doesn't have -mtune. So this should be -mcpu=i686 -march=486. Looking at config.gcc the TARGET_CPU_DEFAULT is overwritten by the target_alias. Looking at i386.c:1038 the cpu string (tuning) is set to the TARGET_DEFAULT, but the arch string remains at i386. the correct way to tune for i686 and use insn for i486 seems to be this one. do you agree? --- gcc/config/i386/i386.c~ 2003-07-09 07:45:00.000000000 +0200 +++ gcc/config/i386/i386.c 2003-08-09 12:58:33.000000000 +0200 @@ -1038,9 +1038,9 @@ if (!ix86_cpu_string && ix86_arch_string) ix86_cpu_string = ix86_arch_string; if (!ix86_cpu_string) - ix86_cpu_string = cpu_names [TARGET_CPU_DEFAULT]; + ix86_cpu_string = cpu_names [TARGET_CPU_DEFAULT_pentiumpro]; if (!ix86_arch_string) - ix86_arch_string = TARGET_64BIT ? "athlon-4" : "i386"; + ix86_arch_string = TARGET_64BIT ? "athlon-4" : "i486"; if (ix86_cmodel_string != 0) {