Simplify type-specifier parsing.

Previously, the tentative parses for optional type-specifier and to support
class template argument deduction were combined awkwardly.  This
reorganization was motivated by the new concepts branch.

	* parser.c (cp_parser_simple_type_specifier): Separate tentative
	parses for optional type-spec and CTAD.

From-SVN: r273514

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index bd85c705629cf0d5810ffdd711a8f8c8901f1f50..ad7f4a3ae1f0edb2a2e04b35e93461cb640f9393 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2019-07-16  Jason Merrill  <jason@redhat.com>
 
+       * parser.c (cp_parser_simple_type_specifier): Separate tentative
+       parses for optional type-spec and CTAD.
+
        * parser.c (cp_parser_nested_name_specifier_opt): If the token is
        already CPP_NESTED_NAME_SPECIFIER, leave it alone.
 

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 14a2168eb6d35b9865abf4b734408d5f49e16fc1..5e4b45391d5be44f22f78cb3a0f9e7dd70ee86a6 100644 (file)
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -17833,7 +17833,7 @@ cp_parser_simple_type_specifier (cp_parser* parser,
 
       /* Don't gobble tokens or issue error messages if this is an
         optional type-specifier.  */
-      if ((flags & CP_PARSER_FLAGS_OPTIONAL) || cxx_dialect >= cxx17)
+      if (flags & CP_PARSER_FLAGS_OPTIONAL)
        cp_parser_parse_tentatively (parser);
 
       token = cp_lexer_peek_token (parser->lexer);
@@ -17873,37 +17873,26 @@ cp_parser_simple_type_specifier (cp_parser* parser,
              else
                {
                  cp_parser_error (parser, "expected template-id for type");
-                 type = NULL_TREE;
+                 type = error_mark_node;
                }
            }
        }
-      /* Otherwise, look for a type-name.  */
-      else
-       type = cp_parser_type_name (parser, (qualified_p && typename_p));
 
-      /* Keep track of all name-lookups performed in class scopes.  */
-      if (type
-         && !global_p
-         && !qualified_p
-         && TREE_CODE (type) == TYPE_DECL
-         && identifier_p (DECL_NAME (type)))
-       maybe_note_name_used_in_class (DECL_NAME (type), type);
-      /* If it didn't work out, we don't have a TYPE.  */
-      if (((flags & CP_PARSER_FLAGS_OPTIONAL) || cxx_dialect >= cxx17)
-         && !cp_parser_parse_definitely (parser))
-       type = NULL_TREE;
-      if (!type && cxx_dialect >= cxx17)
+      /* Otherwise, look for a type-name.  */
+      if (!type)
        {
-         if (flags & CP_PARSER_FLAGS_OPTIONAL)
+         if (cxx_dialect >= cxx17)
            cp_parser_parse_tentatively (parser);
 
-         cp_parser_global_scope_opt (parser,
-                                     /*current_scope_valid_p=*/false);
-         cp_parser_nested_name_specifier_opt (parser,
-                                              /*typename_keyword_p=*/false,
-                                              /*check_dependency_p=*/true,
-                                              /*type_p=*/false,
-                                              /*is_declaration=*/false);
+         type = cp_parser_type_name (parser, (qualified_p && typename_p));
+
+         if (cxx_dialect >= cxx17 && !cp_parser_parse_definitely (parser))
+           type = NULL_TREE;
+       }
+
+      if (!type && cxx_dialect >= cxx17)
+       {
+         /* Try class template argument deduction.  */
          tree name = cp_parser_identifier (parser);
          if (name && TREE_CODE (name) == IDENTIFIER_NODE
              && parser->scope != error_mark_node)
@@ -17929,11 +17918,21 @@ cp_parser_simple_type_specifier (cp_parser* parser,
            }
          else
            type = error_mark_node;
-
-         if ((flags & CP_PARSER_FLAGS_OPTIONAL)
-             && !cp_parser_parse_definitely (parser))
-           type = NULL_TREE;
        }
+
+      /* If it didn't work out, we don't have a TYPE.  */
+      if ((flags & CP_PARSER_FLAGS_OPTIONAL)
+         && !cp_parser_parse_definitely (parser))
+       type = NULL_TREE;
+
+      /* Keep track of all name-lookups performed in class scopes.  */
+      if (type
+         && !global_p
+         && !qualified_p
+         && TREE_CODE (type) == TYPE_DECL
+         && identifier_p (DECL_NAME (type)))
+       maybe_note_name_used_in_class (DECL_NAME (type), type);
+
       if (type && decl_specs)
        cp_parser_set_decl_spec_type (decl_specs, type,
                                      token,