* mangle.c (mangle_decl): Only emit -Wc++1z-compat warnings for
	public or external symbols.

	* g++.dg/cpp1z/noexcept-type14.C: New test.
	* g++.dg/asan/asan_test.C: Remove -Wno-c++1z-compat from dg-options.

From-SVN: r242042