PR preprocessor/12935 preprocessor/12952 preprocessor/13046

PR preprocessor/12935 preprocessor/12952 preprocessor/13046

	PR preprocessor/12935 preprocessor/12952 preprocessor/13046
	* cpplib.c (prepare_directive_trad): Clear skipping only in
	#if and #elif directives.
	(do_undef): Call the handler even if the identifier is not a macro.
	* cpptrad.c (scan_parameters): Emit an error message.
	(_cpp_create_trad_definition): Remember the params list even on
	failure.
	* testsuite/gcc.dg/cpp/trad/macro.c: New tests.

From-SVN: r74562