* lib/file-format.exp (gcc_target_object_format): Use
	${tool}_target_compile, not gcc_target_compile.
	* lib/target-supports.exp (check_alias_available): Likewise.
	(check_gc_sections_available): Likewise.
	* g++.dg/ext/attrib10.C: Use dg-require-alias.
	* g++.old-deja/g++.ext/attrib5.C: Use dg-require-weak and
	dg-require-alias.

From-SVN: r77295