15:24 John Baldwin (jhb) 

devel/freebsd-gcc12: Use -stdlib=libc++ to use libc++.

Instead of overriding the path and library name of libstdc++, set the
path for libc++ and change the default of -stdlib= from libstdc++ to
libc++.

    e858e20

17:27 John Baldwin (jhb) 

devel/freebsd-gcc12: External FreeBSD toolchain based on GCC 12.

This port provides external GCC toolchains for GCC 12.1.0 for the
aarch64, amd64, armv6, armv7, i386, powerpc, powerpc64, and riscv64
platforms.

Reviewed by:	lwhsu
Differential Revision:	https://reviews.freebsd.org/D35685

    fabbde5