[LEDE-DEV] [RFC] toolchain: fix GCC version check causing failure on Debian Testing with gcc-7

[Jo-Philipp Wich]

Hi Peter,

> In Debian there were/are gcc-4.2 .. gcc-4.9, gcc-5 .. gcc-7.
> And what about beauties like 'x86_64-linux-gnu-gcc-7'?
> Why not ditch the 'gcc* --version' invocations and have people use
> 'CC=fancy-named-gcc' on the command line if needed?

That should already work (after fixing the version regex). The build
system will call "$(CC) -dumpversion" and symlink that to
./staging_dir/host/bin/gcc if passing the check, so the extra "gcc-7"
patch hunk should not be needed if you're fine with invoking the
buildroot using "CC=gcc-7 make ...".

I'm fine with removing the version checks entirely if we find an
alternative to check for GCC > 4.8 - maybe a feature test of some sort?

~ Jo