C++11: Fix parsing of trailing-type-specifier.

In particular "auto foo() -> typename Foo<T>::X;" didn't parse.

Change-Id: I7665c9b387e222e4107f053a529d502813ebf617
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/libs/3rdparty/cplusplus/Parser.cpp

@@ -1314,31 +1314,47 @@ bool Parser::parseTemplateArgument(ExpressionAST *&node)
     return parsed;
 }
 
+/** Parses a sequence of
+ *
+ * storage-class-specifier (unless noStorageSpecifier is true)
+ * trailing-type-specifier, which contains
+ *     cv-qualifier
+ *     simple-type-specifier
+ *     typename-specifier
+ *     elaborated-type-specifier
+ *
+ * If onlySimpleTypeSpecifiers is true, it only eats simple-type-specifiers
+ * and cv-qualifiers.
+ */
 bool Parser::parseDeclSpecifierSeq(SpecifierListAST *&decl_specifier_seq,
-                                   bool onlyTypeSpecifiers,
-                                   bool simplified)
+                                   bool noStorageSpecifiers,
+                                   bool onlySimpleTypeSpecifiers)
 {
     DEBUG_THIS_RULE();
     bool has_type_specifier = false;
     NameAST *named_type_specifier = 0;
     SpecifierListAST **decl_specifier_seq_ptr = &decl_specifier_seq;
     for (;;) {
-        if (lookAtCVQualifier()) {
+        if (! noStorageSpecifiers && ! onlySimpleTypeSpecifiers && lookAtStorageClassSpecifier()) {
+            // storage-class-specifier
             SimpleSpecifierAST *spec = new (_pool) SimpleSpecifierAST;
             spec->specifier_token = consumeToken();
             *decl_specifier_seq_ptr = new (_pool) SpecifierListAST(spec);
             decl_specifier_seq_ptr = &(*decl_specifier_seq_ptr)->next;
-        } else if (! onlyTypeSpecifiers && lookAtStorageClassSpecifier()) {
+        } else if (lookAtCVQualifier()) {
+            // cv-qualifier
             SimpleSpecifierAST *spec = new (_pool) SimpleSpecifierAST;
             spec->specifier_token = consumeToken();
             *decl_specifier_seq_ptr = new (_pool) SpecifierListAST(spec);
             decl_specifier_seq_ptr = &(*decl_specifier_seq_ptr)->next;
         } else if (! named_type_specifier && lookAtBuiltinTypeSpecifier()) {
+            // parts of simple-type-specifier
             parseBuiltinTypeSpecifier(*decl_specifier_seq_ptr);
             decl_specifier_seq_ptr = &(*decl_specifier_seq_ptr)->next;
             has_type_specifier = true;
         } else if (! has_type_specifier && (LA() == T_COLON_COLON ||
                                             LA() == T_IDENTIFIER)) {
+            // parts of simple-type-specifier
             if (! parseName(named_type_specifier))
                 return false;
             NamedTypeSpecifierAST *spec = new (_pool) NamedTypeSpecifierAST;
@@ -1346,9 +1362,9 @@ bool Parser::parseDeclSpecifierSeq(SpecifierListAST *&decl_specifier_seq,
             *decl_specifier_seq_ptr = new (_pool) SpecifierListAST(spec);
             decl_specifier_seq_ptr = &(*decl_specifier_seq_ptr)->next;
             has_type_specifier = true;
-        } else if (! simplified && ! has_type_specifier && (LA() == T_TYPENAME ||
-                                                            LA() == T_ENUM     ||
-                                                            lookAtClassKey())) {
+        } else if (! onlySimpleTypeSpecifiers && ! has_type_specifier &&
+                   (LA() == T_TYPENAME || LA() == T_ENUM || lookAtClassKey())) {
+            // typename-specifier, elaborated-type-specifier
             unsigned startOfElaboratedTypeSpecifier = cursor();
             if (! parseElaboratedTypeSpecifier(*decl_specifier_seq_ptr)) {
                 error(startOfElaboratedTypeSpecifier,
@@ -6472,12 +6488,6 @@ bool Parser::parseTrailingReturnType(TrailingReturnTypeAST *&node)
     return true;
 }
 
-bool Parser::parseTrailingTypeSpecifierSeq(SpecifierListAST *&node)
-{
-    DEBUG_THIS_RULE();
-    return parseSimpleTypeSpecifier(node);
-}
-
 void Parser::rewind(unsigned cursor)
 {
 #ifndef CPLUSPLUS_NO_DEBUG_RULE

src/libs/3rdparty/cplusplus/Parser.h

@@ -167,15 +167,18 @@ public:
     bool parseAttributeSpecifier(SpecifierListAST *&node);
     bool parseAttributeList(AttributeListAST *&node);
 
-    bool parseSimpleTypeSpecifier(SpecifierListAST *&node)
-    { return parseDeclSpecifierSeq(node, true, true); }
+    bool parseDeclSpecifierSeq(SpecifierListAST *&node,
+                               bool noStorageSpecifiers = false,
+                               bool onlySimpleTypeSpecifiers = false);
 
-    bool parseTypeSpecifier(SpecifierListAST *&node)
+    bool parseTrailingTypeSpecifierSeq(SpecifierListAST *&node)
     { return parseDeclSpecifierSeq(node, true); }
+    /// This actually parses a trailing-type-specifier sequence
+    bool parseTypeSpecifier(SpecifierListAST *&node)
+    { return parseTrailingTypeSpecifierSeq(node); }
+    bool parseSimpleTypeSpecifier(SpecifierListAST *&node)
+    { return parseDeclSpecifierSeq(node, true, true); }
 
-    bool parseDeclSpecifierSeq(SpecifierListAST *&node,
-                               bool onlyTypeSpecifiers = false,
-                               bool simplified = false);
     bool parseUnaryExpression(ExpressionAST *&node);
     bool parseUnqualifiedName(NameAST *&node, bool acceptTemplateId = true);
     bool parseUsing(DeclarationAST *&node);
@@ -202,7 +205,6 @@ public:
     bool parseCapture(CaptureAST *&node);
     bool parseCaptureList(CaptureListAST *&node);
     bool parseTrailingReturnType(TrailingReturnTypeAST *&node);
-    bool parseTrailingTypeSpecifierSeq(SpecifierListAST *&node);
 
     // ObjC++
     bool parseObjCExpression(ExpressionAST *&node);

tests/auto/cplusplus/cxx11/data/trailingtypespec.1.cpp

+auto foo()
+    -> const typename XYZ::abc<T>::def;
+
+auto foo()
+    -> class XYZ::def;

tests/auto/cplusplus/cxx11/tst_cxx11.cpp

@@ -152,6 +152,7 @@ void tst_cxx11::parse_data()
     QTest::newRow("packExpansion.1") << "packExpansion.1.cpp" << "";
     QTest::newRow("declType.1") << "declType.1.cpp" << "";
     QTest::newRow("threadLocal.1") << "threadLocal.1.cpp" << "";
+    QTest::newRow("trailingtypespec.1") << "trailingtypespec.1.cpp" << "";
 }
 
 void tst_cxx11::parse()