re PR c++/85265 ([concepts] ICE with missing identifier)

/cp
2018-08-29  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/85265
	* parser.c (cp_parser_introduction_list): If cp_parser_identifier
	returns error_mark_node early exit the loop.
	(cp_parser_template_introduction): Improve error-recovery, remove
	error call about empty introduction-list.

/testsuite
2018-08-29  Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/85265
	* g++.dg/concepts/pr85265.C: New.

From-SVN: r263966

gcc/cp/ChangeLog

+2018-08-29  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/85265
+	* parser.c (cp_parser_introduction_list): If cp_parser_identifier
+	returns error_mark_node early exit the loop.
+	(cp_parser_template_introduction): Improve error-recovery, remove
+	error call about empty introduction-list.
+
 2018-08-29  David Malcolm  <dmalcolm@redhat.com>
 
 	PR c++/85110

gcc/cp/parser.c

@@ -15242,11 +15242,15 @@ cp_parser_introduction_list (cp_parser *parser)
       if (is_pack)
 	cp_lexer_consume_token (parser->lexer);
 
+      tree identifier = cp_parser_identifier (parser);
+      if (identifier == error_mark_node)
+	break;
+
       /* Build placeholder. */
       tree parm = build_nt (WILDCARD_DECL);
       DECL_SOURCE_LOCATION (parm)
 	= cp_lexer_peek_token (parser->lexer)->location;
-      DECL_NAME (parm) = cp_parser_identifier (parser);
+      DECL_NAME (parm) = identifier;
       WILDCARD_PACK_P (parm) = is_pack;
       vec_safe_push (introduction_vec, parm);
 
@@ -27178,18 +27182,18 @@ cp_parser_template_introduction (cp_parser* parser, bool member_p)
      matching identifiers.  */
   tree introduction_list = cp_parser_introduction_list (parser);
 
+  /* Look for closing brace for introduction.  */
+  if (!braces.require_close (parser))
+    return true;
+
   /* The introduction-list shall not be empty.  */
   int nargs = TREE_VEC_LENGTH (introduction_list);
   if (nargs == 0)
     {
-      error ("empty introduction-list");
+      /* In cp_parser_introduction_list we have already issued an error.  */
       return true;
     }
 
-  /* Look for closing brace for introduction.  */
-  if (!braces.require_close (parser))
-    return true;
-
   if (tmpl_decl == error_mark_node)
     {
       cp_parser_name_lookup_error (parser, concept_name, tmpl_decl, NLE_NULL,

gcc/testsuite/ChangeLog

+2018-08-29  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/85265
+	* g++.dg/concepts/pr85265.C: New.
+
 2018-08-29  Martin Sebor  <msebor@redhat.com>
 	    Bernd Edlinger  <bernd.edlinger@hotmail.de>
 

gcc/testsuite/g++.dg/concepts/pr85265.C

+// { dg-do compile { target c++14 } }
+// { dg-additional-options "-fconcepts" }
+
+template<typename> concept bool C = true;
+
+C{} void foo();  // { dg-error "expected identifier" }