PR testsuite/47400
	* lib/target-supports.exp (check_ascii_locale_available): New proc.
	* lib/target-supports-dg.exp (dg-require-ascii-locale): New proc.
	* gcc.dg/attr-alias-5.c: Use dg-require-ascii-locale.
	* gcc.dg/ucnid-10.c: Likewise.
	* gcc.dg/ucnid-13.c: Likewise.
	* gcc.dg/ucnid-7.c: Likewise.
	* gcc.dg/ucnid-8.c: Likewise.
	* Adapt dg-warning line number.

	gcc:
	PR testsuite/47400
	* doc/sourcebuild.texi (Require Support): Document
	dg-require-ascii-locale.

From-SVN: r170046