re PR lto/65316 (LTO: Uninitialized memory / ICE with -g -fno-lto-odr-type-merging...

re PR lto/65316 (LTO: Uninitialized memory / ICE with -g -fno-lto-odr-type-merging: in types_same_for_odr, at ipa-devirt.c:465)

	PR lto/65316
	* ipa-utils.h (types_odr_comparable): Add strict argument.
	* ipa-devirt.c: Fix whitespace;
	(odr_hasher): Remove.
	(odr_name_hasher, odr_vtable_hasher): New hashers.
	(can_be_name_hashed_p): New predicate.
	(hash_type_name): remove.
	(hash_odr_name): New.
	(odr_name_hasher::hash): new.
	(can_be_vtable_hashed_p): New.
	(hash_odr_vtable): New.
	(odr_vtable_hasher::hash): New.
	(types_same_for_odr): Add strict parameter.
	(types_odr_comparable): Likewise.
	(odr_name_hasher::equal): New.
	(odr_vtable_hasher::equal): New.
	(odr_name_hasher::remove): New.
	(odr_hash_type): Change to hash_table<odr_name_hasher>.
	(odr_vtable_hash_type): New.
	(odr_vtable_hash): New.
	(odr_subtypes_equivalent_p): Do strict comparsion.
	(add_type_duplicate): Merge type names; cleanup; avoid type
	duplicates.
	(register_odr_type): Initialize vtable hash.
	(build_type_inheritance_graph): Likewise
	(get_odr_type): Reorg to use two hashes.
	(dump_possible_polymorphic_call_targets): Move sanity check after debug
	output.
	(ipa_devirt): Dump type_inheritance_graph.
	(types_same_for_odr): Add strict mode.
	* g++.dg/lto/pr65316_0.C: New testcase.
	* g++.dg/lto/pr65316_1.C: New testcase.

From-SVN: r221275