[PR c++/84970] lookup marking

https://gcc.gnu.org/ml/gcc-patches/2018-03/msg00973.html
	PR c++/84970
	* cp-tree.h (lookup_list_keep): Declare.
	* tree.c (lookup_list_keep): New, broken out of ...
	(build_min): ... here.  Call it.
	* decl.c (cp_finish_decl): Call lookup_list_keep.

	PR c++/84970
	* g++.dg/lookup/pr84970.C: New.

From-SVN: r258685

gcc/cp/ChangeLog

+2018-03-20  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/84970
+	* cp-tree.h (lookup_list_keep): Declare.
+	* tree.c (lookup_list_keep): New, broken out of ...
+	(build_min): ... here.  Call it.
+	* decl.c (cp_finish_decl): Call lookup_list_keep.
+
 2018-03-19  Jason Merrill  <jason@redhat.com>
 
 	PR c++/84937 - ICE with class deduction and auto.

gcc/cp/cp-tree.h

@@ -7012,6 +7012,7 @@ extern tree lookup_add				(tree fns, tree lookup);
 extern tree lookup_maybe_add			(tree fns, tree lookup,
 						 bool deduping);
 extern void lookup_keep				(tree lookup, bool keep);
+extern void lookup_list_keep			(tree list, bool keep);
 extern int is_overloaded_fn			(tree) ATTRIBUTE_PURE;
 extern bool really_overloaded_fn		(tree) ATTRIBUTE_PURE;
 extern tree dependent_name			(tree);

gcc/cp/decl.c

@@ -7034,7 +7034,11 @@ cp_finish_decl (tree decl, tree init, bool init_const_expr_p,
 	}
 
       if (init)
-	DECL_INITIAL (decl) = init;
+	{
+	  if (TREE_CODE (init) == TREE_LIST)
+	    lookup_list_keep (init, true);
+	  DECL_INITIAL (decl) = init;
+	}
       if (dep_init)
 	{
 	  retrofit_lang_decl (decl);

gcc/cp/tree.c

@@ -2436,6 +2436,20 @@ lookup_keep (tree lookup, bool keep)
     ovl_used (lookup);
 }
 
+/* LIST is a TREE_LIST whose TREE_VALUEs may be OVERLOADS that need
+   keeping, or may be ignored.  */
+
+void
+lookup_list_keep (tree list, bool keep)
+{
+  for (; list; list = TREE_CHAIN (list))
+    {
+      tree v = TREE_VALUE (list);
+      if (TREE_CODE (v) == OVERLOAD)
+	lookup_keep (v, keep);
+    }
+}
+
 /* Returns nonzero if X is an expression for a (possibly overloaded)
    function.  If "f" is a function or function template, "f", "c->f",
    "c.f", "C::f", and "f<int>" will all be considered possibly
@@ -3315,9 +3329,7 @@ build_min (enum tree_code code, tree tt, ...)
 
   if (code == CAST_EXPR)
     /* The single operand is a TREE_LIST, which we have to check.  */
-    for (tree v = TREE_OPERAND (t, 0); v; v = TREE_CHAIN (v))
-      if (TREE_CODE (TREE_VALUE (v)) == OVERLOAD)
-	lookup_keep (TREE_VALUE (v), true);
+    lookup_list_keep (TREE_OPERAND (t, 0), true);
 
   return t;
 }

gcc/testsuite/ChangeLog

+2018-03-20  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/84970
+	* g++.dg/lookup/pr84970.C: New.
+
 2018-03-20  Richard Biener  <rguenther@suse.de>
 
 	PR target/84986

gcc/testsuite/g++.dg/lookup/pr84970.C

+// PR c++/84970 ICE with deferred initializer
+
+namespace bob {
+  void a();
+}
+using namespace bob;
+
+void a (int);
+
+template <typename b>
+void *x (b)
+{
+  void (*c)(b) (a);
+
+  return (void *)c;
+}
+
+void d () {
+  x (1);
+}
+