re PR c++/80956 (ICE with abstract class vector)

/cp
2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/80956
	* call.c (convert_like_real): Fail gracefully for a broken
	std::initializer_list, missing a definition.

	* name-lookup.c (do_pushtag): Tweak message, use %< and %>.

/testsuite
2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/80956
	* g++.dg/cpp0x/initlist100.C: New.
	* g++.dg/cpp0x/initlist101.C: Likewise.

From-SVN: r259137

gcc/cp/ChangeLog

 2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>
 
+	PR c++/80956
+	* call.c (convert_like_real): Fail gracefully for a broken
+	std::initializer_list, missing a definition.
+
+	* name-lookup.c (do_pushtag): Tweak message, use %< and %>.
+
+2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>
+
 	PR c++/84792
 	* decl.c (grokdeclarator): Fix diagnostic about typedef name used
 	as nested-name-specifier, keep type and TREE_TYPE (decl) in sync.

gcc/cp/call.c

@@ -6880,8 +6880,12 @@ convert_like_real (conversion *convs, tree expr, tree fn, int argnum,
 	if (array == error_mark_node)
 	  return error_mark_node;
 
-	/* Build up the initializer_list object.  */
-	totype = complete_type (totype);
+	/* Build up the initializer_list object.  Note: fail gracefully
+	   if the object cannot be completed because, for example, no
+	   definition is provided (c++/80956).  */
+	totype = complete_type_or_maybe_complain (totype, NULL_TREE, complain);
+	if (!totype)
+	  return error_mark_node;
 	field = next_initializable_field (TYPE_FIELDS (totype));
 	CONSTRUCTOR_APPEND_ELT (vec, field, array);
 	field = next_initializable_field (DECL_CHAIN (field));

gcc/cp/name-lookup.c

@@ -6476,8 +6476,8 @@ do_pushtag (tree name, tree type, tag_scope scope)
 	      && init_list_identifier == DECL_NAME (TYPE_NAME (type))
 	      && !CLASSTYPE_TEMPLATE_INFO (type))
 	    {
-	      error ("declaration of std::initializer_list does not match "
-		     "#include <initializer_list>, isn't a template");
+	      error ("declaration of %<std::initializer_list%> does not match "
+		     "%<#include <initializer_list>%>, isn't a template");
 	      return error_mark_node;
 	    }
 	}

gcc/testsuite/ChangeLog

 2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>
 
+	PR c++/80956
+	* g++.dg/cpp0x/initlist100.C: New.
+	* g++.dg/cpp0x/initlist101.C: Likewise.
+
+2018-04-05  Paolo Carlini  <paolo.carlini@oracle.com>
+
 	PR c++/84792
 	* g++.dg/other/pr84792-1.C: New.
 	* g++.dg/other/pr84792-2.C: Likewise.

gcc/testsuite/g++.dg/cpp0x/initlist100.C

+// PR c++/80956
+// { dg-do compile { target c++11 } }
+
+namespace std {
+template <class> class initializer_list;  // { dg-message "declaration" }
+}
+
+template <typename T> struct B { B (std::initializer_list<T>); };
+struct C { virtual int foo (); };
+struct D : C {} d { B<C> { D {} } };  // { dg-error "incomplete|no matching" }

gcc/testsuite/g++.dg/cpp0x/initlist101.C

+// PR c++/80956
+// { dg-do compile { target c++11 } }
+
+#include <initializer_list>
+
+template <typename T> struct B { B (std::initializer_list<T>); };
+struct C { virtual int foo (); };
+struct D : C {} d { B<C> { D {} } };  // { dg-error "no matching" }