PR c++/41090

	Add -fdeclone-ctor-dtor.
gcc/cp/
	* optimize.c (can_alias_cdtor, populate_clone_array): Split out
	from maybe_clone_body.
	(maybe_thunk_body): New function.
	(maybe_clone_body): Call it.
	* mangle.c (write_mangled_name): Remove code to suppress
	writing of mangled name for cloned constructor or destructor.
	(write_special_name_constructor): Handle decloned constructor.
	(write_special_name_destructor): Handle decloned destructor.
	* method.c (trivial_fn_p): Handle decloning.
	* semantics.c (expand_or_defer_fn_1): Clone after setting linkage.
gcc/c-family/
	* c.opt: Add -fdeclone-ctor-dtor.
	* c-opts.c (c_common_post_options): Default to on iff -Os.
gcc/
	* cgraph.h (struct cgraph_node): Add calls_comdat_local.
	(symtab_comdat_local_p, symtab_in_same_comdat_p): New.
	* cif-code.def: Add USES_COMDAT_LOCAL.
	* symtab.c (verify_symtab_base): Make sure we don't refer to a
	comdat-local symbol from outside its comdat.
	* cgraph.c (verify_cgraph_node): Likewise.
	* cgraphunit.c (mark_functions_to_output): Don't mark comdat-locals.
	* ipa.c (symtab_remove_unreachable_nodes): Likewise.
	(function_and_variable_visibility): Handle comdat-local fns.
	* ipa-cp.c (determine_versionability): Don't clone comdat-locals.
	* ipa-inline-analysis.c (compute_inline_parameters): Update
	calls_comdat_local.
	* ipa-inline-transform.c (inline_call): Likewise.
	(save_inline_function_body): Don't clear DECL_COMDAT_GROUP.
	* ipa-inline.c (can_inline_edge_p): Check calls_comdat_local.
	* lto-cgraph.c (input_overwrite_node): Read calls_comdat_local.
	(lto_output_node): Write it.
	* symtab.c (symtab_dissolve_same_comdat_group_list): Clear
	DECL_COMDAT_GROUP for comdat-locals.
include/
	* demangle.h (enum gnu_v3_ctor_kinds):
	Added literal gnu_v3_unified_ctor.
	(enum gnu_v3_ctor_kinds):
	Added literal gnu_v3_unified_dtor.
libiberty/
	* cp-demangle.c (cplus_demangle_fill_ctor,cplus_demangle_fill_dtor):
	Handle unified ctor/dtor.
	(d_ctor_dtor_name): Handle unified ctor/dtor.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@206182 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 7 insertions, 4 deletions

diff --git a/gcc/ipa.c b/gcc/ipa.c
index 1ec4b5fc3b7..3c19288f26c 100644
--- a/gcc/ipa.c
+++ b/gcc/ipa.c
@@ -362,14 +362,17 @@ symtab_remove_unreachable_nodes (bool before_inlining_p, FILE *file)
 	      enqueue_node (origin_node, &first, reachable);
 	    }
 	  /* If any symbol in a comdat group is reachable, force
-	     all other in the same comdat group to be also reachable.  */
+	     all externally visible symbols in the same comdat
+	     group to be reachable as well.  Comdat-local symbols
+	     can be discarded if all uses were inlined.  */
 	  if (node->same_comdat_group)
 	    {
 	      symtab_node *next;
 	      for (next = node->same_comdat_group;
 		   next != node;
 		   next = next->same_comdat_group)
-		if (!pointer_set_insert (reachable, next))
+		if (!symtab_comdat_local_p (next)
+		    && !pointer_set_insert (reachable, next))
 		  enqueue_node (next, &first, reachable);
 	    }
 	  /* Mark references as reachable.  */
@@ -969,14 +972,14 @@ function_and_variable_visibility (bool whole_program)
 	  node->unique_name = ((node->resolution == LDPR_PREVAILING_DEF_IRONLY
 				      || node->resolution == LDPR_PREVAILING_DEF_IRONLY_EXP)
 				      && TREE_PUBLIC (node->decl));
-	  symtab_make_decl_local (node->decl);
 	  node->resolution = LDPR_PREVAILING_DEF_IRONLY;
-	  if (node->same_comdat_group)
+	  if (node->same_comdat_group && TREE_PUBLIC (node->decl))
 	    /* cgraph_externally_visible_p has already checked all other nodes
 	       in the group and they will all be made local.  We need to
 	       dissolve the group at once so that the predicate does not
 	       segfault though. */
 	    symtab_dissolve_same_comdat_group_list (node);
+	  symtab_make_decl_local (node->decl);
 	}
 
       if (node->thunk.thunk_p