Obtaining current GCC architecture

Question

How can I find out what the -march default argument is for the current architecture if I don\'t supply any?

Answer 1

You can use gcc -Q --help= to list the current option values of the given . Thus:

$ gcc -Q --help=target | grep march
  -march=                           x86-64
$ gcc -m32 -Q --help=target | grep march
  -march=                           i686
$ i686-w64-mingw32-gcc -Q --help=target | grep march
  -march=                           pentiumpro

Edit: Actually, this option is not as generally useful as it appears, because target-specific defaults are not reflected in the output.