re PR c++/77626 (ICE with -Wall on x86_64-linux-gnu (internal compiler error: Segmentation fault, byte_from_pos, cxx_fold_indirect_ref))

	PR c++/77626
	* constexpr.c (cxx_fold_indirect_ref): Don't call byte_position on
	FIELD_DECLs with error_mark_node type.  Remove useless break; after
	return.

	* g++.dg/other/pr77626.C: New test.

From-SVN: r240267