openmp: Ensure proper diagnostics for -> in map/to/from clauses [PR104532]

openmp: Ensure proper diagnostics for -> in map/to/from clauses [PR104532]

The following patch uses the functions normal CPP_DEREF parsing uses,
i.e. convert_lvalue_to_rvalue and build_indirect_ref, instead of
blindly calling build_simple_mem_ref, so that if the variable does not
have correct type, we properly diagnose it instead of ICEing on it.

2022-02-17  Jakub Jelinek  <jakub@redhat.com>

	PR c/104532
	* c-parser.cc (c_parser_omp_variable_list): For CPP_DEREF, use
	convert_lvalue_to_rvalue and build_indirect_ref instead of
	build_simple_mem_ref.

	* gcc.dg/gomp/pr104532.c: New test.