https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81519
--- Comment #7 from Daniel Santos <daniel.santos at pobox dot com> --- (In reply to Martin Liška from comment #4) > Ok, so I've briefly investigated source code and providing such information > is definitely not a simple task :/ > > I would recommend to fix PR39851 and then one will just compare output of > following 2 invocations: > > gcc --help=target -Q > gcc --help=target -march=native -Q > > Will it work for you? > > Note that fully understand which ISA extensions are enable when is also > quite complex. I've thought about this some more and I'm starting to think that all of this can be determined with a script that iteratively calls gcc --help=target -Q with various machine flags to determine which -mno-* flags are really needed and which -m<isa> flags include others. So in effect, I'm thinking that we can produce optimal C(XX)FLAGS with a script and your PR39851 fix. I'll have to test this out. Thanks
