[Bug fortran/80889] New: [8 Regression] Bootstrap broken on all targets due to rev 248472

[wilco at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80889

            Bug ID: 80889
           Summary: [8 Regression] Bootstrap broken on all targets due to
                    rev 248472
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: blocker
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: wilco at gcc dot gnu.org
  Target Milestone: ---

As reported in https://gcc.gnu.org/ml/gcc-patches/2017-05/msg01995.html all
bootstraps fail:

configure: error: conditional "HAVE_AVX128" was never defined.
Usually this means the macro was only invoked conditionally.
Makefile:19843: recipe for target 'configure-target-libgfortran' failed
make[1]: *** [configure-target-libgfortran] Error 1
make[1]: *** Waiting for unfinished jobs....

Even if you disable this error, bootstrap fails due to trying to build x86
specific files:

gcc/libgfortran/generated/matmulavx128_i1.c  -fPIC -DPIC -o
.libs/matmulavx128_i1.o
xgcc: error: unrecognized command line option ‘-mprefer-avx128’
make[3]: *** [matmulavx128_i1.lo] Error 1