PR ipa/63622

        PR ipa/63795
	* g++.dg/ipa/ipa-icf-4.C: Add more precise dump scan.
	* g++.dg/ipa/ipa-icf-5.C: Add condition for target
	with symbol alias support.
	* ipa-icf.c (sem_function::merge): Add new target symbol alias
	support guard.
	(sem_variable::merge): Likewise.
	* ipa-icf.h (target_supports_symbol_aliases_p): New function.

From-SVN: r217355