Dear all,

I'd like to commit the attached patch as obvious within the next 24 hours
unless anybody objects, or earlier if there is positive feedback.

The patch only fixes three obvious NULL pointer dereferences that were
latent before the referenced commit and exhibited in the testcases,
see PRs.

The submitted testcases in the PRs hint at unimplemented parts of the
F2018 standard in gfortran.  I consider it unlikely that these parts are
written before 12-release, so fixing the ICE is something that can be
done now.  After that, either the regression marker can be removed from
the PRs, or they are closed and the remaining issues moved to a new PR.

Regtested on x86_64-pc-linux-gnu.  Comments welcome.

Thanks,
Harald