builtins.c (validate_gimple_arglist): Don't use va_arg with enum type.

builtins.c (validate_gimple_arglist): Don't use va_arg with enum type.

./:	* builtins.c (validate_gimple_arglist): Don't use va_arg with
	enum type.
	* calls.c (emit_library_call_value_1): Likewise.

	* c-typeck.c (c_build_va_arg): New function.
	* c-tree.h (c_build_va_arg): Declare.
	* c-parser.c (c_parser_postfix_expression): Call c_build_va_arg
	instead of build_va_arg.
cp/:
	* error.c (cp_printer): Don't use va_arg with enum type.
testsuite/:
	* gcc.dg/Wcxx-compat-11.c: New testcase.

From-SVN: r147989