To use the modern form when possible. The modern option also allows
using the `no-` prefix to disable.
Supported by: gcc 4.8+, clang 3.2+ (= appleclang 4.2+)
This also automatically changes `-clang:-pedantic` to `-Wpedantic` in
clang-cl builds.
Refs:
9877f689f2https://gcc.gnu.org/onlinedocs/gcc-4.8.5/gcc/Warning-Options.htmlCloses#20010