[Bug target/80782] Feature request: use the llvm/clang assembler on Mac

["rjvbertin at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80782

--- Comment #4 from René J.V. Bertin <rjvbertin at gmail dot com> ---
The current support apparently has its glitches but above all it has nothing to
do with gcc itself; it consists of using an existing `as` option to "Use  the 
clang(1) integrated assembler instead of the GNU based system assembler".
That's apparently the default for `as` so I don't understand why it doesn't
invoke clang when used through gcc.

> So, what is the correct configure option to let gcc use it by default?

Write a wrapper script that just prepends or appends `-q` to the arguments and
then calls the actual `as` command, and use that wrapper with the `--with-as`
option? Crossing fingers that GCC itself will build...

What I had in mind was calling `clang -cc1as` or even `llvm-as` directly, with
the proper arguments. That ought to give better control over the generated
object code than relying on a 3rd party (Apple) to implement the GNU -> clang
argument translation.