re PR c++/46538 (ICE: SIGSEGV in cp_make_fname_decl (decl.c:3690) on invalid code when using __PRETTY_FUNCTION__)

	PR c++/46538
	* decl.c (cp_make_fname_decl): Return error_mark_node if
	current_binding_level has already sk_function_parms kind.

	* g++.dg/other/error34.C: New test.

From-SVN: r166974