https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116119
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
>--prefix=${PREFIX}--with-arch=armv8-a
There is a space missing between the configure options in your binutils
configure which I suspect is the issue as the assembler is NOT being found.