[Bug testsuite/85326] `make check` fails with `--disable-bootstrap` and `--enable-languages=c`

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85326

--- Comment #2 from ktkachov at gcc dot gnu.org ---
(In reply to Jakub Jelinek from comment #1)
> gcc.target/arm/pr56184.C
> gcc.target/arm/pr59985.C
> gcc.target/arm/pr67989.C
> gcc.target/arm/pr54300.C
> gcc.target/arm/pr55073.C
> gcc.target/s390/pr77822-1.C
> gcc.target/x86_64/abi/ms-sysv/gen.cc
> gcc.target/i386/mpx/chkp-thunk-comdat-1.cc
> gcc.target/i386/mpx/pr66048.cc
> gcc.target/i386/mpx/chkp-thunk-comdat-2.cc
> gcc.target/i386/mpx/pr65531.cc
> gcc.target/powerpc/undef-bool-1.C
> gcc.target/aarch64/pr60675.C
> gcc.target/aarch64/pr81414.C
> gcc.target/aarch64/simd/pr67896.C
> gcc.target/aarch64/sve/const_pred_2.C
> gcc.target/aarch64/sve/vcond_1.C
> gcc.target/aarch64/sve/const_pred_4.C
> gcc.target/aarch64/sve/vcond_1_run.C
> gcc.target/aarch64/sve/const_pred_1.C
> gcc.target/aarch64/sve/tls_2.C
> gcc.target/aarch64/sve/const_pred_3.C
> gcc.target/aarch64/pr81422.C
> 
> tests are broken this way.  I think ms-sysv/gen.cc is probably ok, as it
> just a generator and built with $HOSTCXX rather than target g++.  mpx is
> deprecated and going to be removed in GCC 9, so there is no point trying to
> deal with it.
> arm, s390, aarch64 and powerpc should fix their testsuite.

I think some of the arm tests could well be C tests rather than C++. So maybe
just renaming the file to *.c will be enough.

For the ones that are truly C++ is the recommended approach moving them to
g++.dg and guarding them on the target?