re PR lto/45736 (ICE: in cgraph_remove_unreachable_nodes, at ipa.c:245 with -flto and attribute((constructor)))


	PR middle-end/45736
	* cgraph.c (cgraph_set_readonly_flag): Rename to...
	(cgraph_set_const_flags) ... this one; get also looping argument;
	clear constructor/destructor flags.
	(cgraph_set_pure_flag): Likewise.
	(cgraph_set_looping_const_or_pure_flag): Remove.
	(cgraph_can_remove_if_no_direct_calls_and_refs): Do not try
	to optimize away static ctors/dtors; it does not work on inline clones;
	external functions can always be rmeoved.
	(cgraph_will_be_removed_from_program_if_no_direct_calls): Assert on inline
	clones; in LTO external functions always can go.
	(cgraph_used_from_object_file_p): Handle EXTERNAL functions correctly.
	(cgraph_mark_address_taken_node): Assert that we are not taking address of
	inline clone.
	(cgraph_can_remove_if_no_direct_calls_p): We always eventually remove
	external functions.
	* ipa-cp.c (ipcp_cloning_candidate_p): Do not clone functions with address taken.
	(ipcp_initialize_node_lattices): Only local functions can be handled without cloning.
	* cgraph.h (cgraph_set_readonly_flag,
	cgraph_set_looping_const_or_pure_flag): Remove.
	(cgraph_set_const_flag): Declare.
	(cgraph_set_pure_flag): Update.
	* ipa-pure-const (propagate_pure_const, local_pure_const): Update
	flags setting code.
	* ipa.c (cgraph_remove_unreachable_nodes): Fix formating; do not look at inline
	clones; fix handling of external definitions.
	(cgraph_postorder): Do not look at inline clones in the first pass.
	(function_and_variable_visibility): Drop constructors/destructor
	flags at pure and const functions.
	* tree-profile.c (tree_profiling): Update.
	* ipa-inline.c (cgraph_clone_inlined_nodes): Always clone functions with
	address taken; external functions do not account to whole program size.
	(cgraph_decide_inlining): Likewise; do not try to inline functions already
	inlined.
	* testsuite/gcc.dg/lto/pr45736_0.c: New function.

From-SVN: r165972