* ipa-utils.h (warn_types_mismatch, odr_or_derived_type_p,
	odr_types_equivalent_p): Declare.
	(odr_type_p): Use gcc_checking_assert.
	(type_in_anonymous_namespace_p) Declare.
	(type_with_linkage_p): Declare.
	* common.opt (Wlto-type-mismatch): New warning.
	* ipa-devirt.c (compound_type_base): New function.
	(odr_or_derived_type_p): New function.
	(odr_types_equivalent_p): New function.
	(add_type_duplicate): Simplify.
	(type_with_linkage_p): Add hack to prevent false positives on C types
	(type_in_anonymous_namespace_p): Likewise.
	* tree.c (need_assembler_name_p): Use type_with_linkage.
	* tree.h (type_in_anonymous_namespace_p): Remove.
	* doc/invoke.texi (-Wlto-type-mismatch): Document

	* lto-symtab.c (warn_type_compatibility_p): Break out from ...;
	compare ODR types (if available) and function types.
	(lto_symtab_merge): ... here; output ODR violation warnings
	and call warn_types_mismatch.

	* gfortran.dg/lto/20091028-2_1.c: Fix return value.
	* gfortran.dg/lto/pr41576_1.f90: Add interface.
	* gfortran.dg/lto/pr41521_0.f90: Disable lto-type-mismatch
	* gfortran.dg/lto/pr60635_0.f90: Disable lto-type-mismatch.
	* gfortran.dg/lto/20091028-1_1.c: Fix return type.
	* gcc.dg/lto/20120723_0.c: Disbale lto-type-mismatch.

From-SVN: r223258