re PR fortran/91942 (ICE in match_vtag, at fortran/io.c:1485)

re PR fortran/91942 (ICE in match_vtag, at fortran/io.c:1485)

2019-10-02  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/91942
	* io.c (match_vtag): Check for non-NULL result->symtree.
	(match_out_tag): Check for invalid constant due to inquiry parameter.
	(match_filepos): Instead of a syntax error, go to cleanup to get better
	error messages.

2019-10-02  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/91942
	* gfortran.dg/pr91587.f90: Update dg-error regex.
	* gfortran.dg/pr91942.f90: New test.

From-SVN: r276472