https://gcc.gnu.org/bugzilla/show_bug.cgi?id=38959
Alexander Monakov <amonakov at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED CC| |amonakov at gcc dot gnu.org Resolution|--- |INVALID --- Comment #5 from Alexander Monakov <amonakov at gcc dot gnu.org> --- As far as I can tell this report was not correctly triaged 10 years ago, as that's exactly what -mtune= is for: optimize for a given CPU without assuming availability of its ISA extensions. So from compiler perspective something like -march=i386 -mtune=i486 gives the requested behavior, and any strict enforcement is a job for the assembler, not the compiler. So let's close as invalid.