Disambiguation of '[[':

 * In C++11, '[[' is ill-formed unless it starts an attribute-specifier. Reject
   array sizes and array indexes which begin with a lambda-expression. Recover by
   parsing the lambda as a lambda.
 * In Objective-C++11, either '[' could be the start of a message-send.
   Fully disambiguate this case: it turns out that the grammars of message-sends,
   lambdas and attributes do not actually overlap. Accept any occurrence of '[['
   where either '[' starts a message send, but reject a lambda in an array index
   just like in C++11 mode.

Implement a couple of changes to the attribute wording which occurred after our
attributes implementation landed:
 * In a function-declaration, the attributes go after the exception specification,
   not after the right paren.
 * A reference type can have attributes applied.
 * An 'identifier' in an attribute can also be a keyword. Support for alternative
   tokens (iso646 keywords) in attributes to follow.

And some bug fixes:
 * Parse attributes after declarator-ids, even if they are not simple identifiers.
 * Do not accept attributes after a parenthesized declarator.
 * Accept attributes after an array size in a new-type-id.
 * Partially disamiguate 'delete' followed by a lambda. More work is required
   here for the case where the lambda-introducer is '[]'.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@154369 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 17 insertions, 4 deletions

diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index 0b7b2d9668..2af74824eb 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -1817,7 +1817,9 @@ bool Parser::ParseUnqualifiedIdOperator(CXXScopeSpec &SS, bool EnteringContext,
       bool isNew = Tok.getKind() == tok::kw_new;
       // Consume the 'new' or 'delete'.
       SymbolLocations[SymbolIdx++] = ConsumeToken();
-      if (Tok.is(tok::l_square)) {
+      // Check for array new/delete.
+      if (Tok.is(tok::l_square) &&
+          (!getLangOpts().CPlusPlus0x || NextToken().isNot(tok::l_square))) {
         // Consume the '[' and ']'.
         BalancedDelimiterTracker T(*this, tok::l_square);
         T.consumeOpen();
@@ -2346,6 +2348,10 @@ void Parser::ParseDirectNewDeclarator(Declarator &D) {
   // Parse the array dimensions.
   bool first = true;
   while (Tok.is(tok::l_square)) {
+    // An array-size expression can't start with a lambda.
+    if (CheckProhibitedCXX11Attribute())
+      continue;
+
     BalancedDelimiterTracker T(*this, tok::l_square);
     T.consumeOpen();
 
@@ -2360,13 +2366,16 @@ void Parser::ParseDirectNewDeclarator(Declarator &D) {
 
     T.consumeClose();
 
-    ParsedAttributes attrs(AttrFactory);
+    // Attributes here appertain to the array type. C++11 [expr.new]p5.
+    ParsedAttributes Attrs(AttrFactory);
+    MaybeParseCXX0XAttributes(Attrs);
+
     D.AddTypeInfo(DeclaratorChunk::getArray(0,
                                             /*static=*/false, /*star=*/false,
                                             Size.release(),
                                             T.getOpenLocation(),
                                             T.getCloseLocation()),
-                  attrs, T.getCloseLocation());
+                  Attrs, T.getCloseLocation());
 
     if (T.getCloseLocation().isInvalid())
       return;
@@ -2418,7 +2427,11 @@ Parser::ParseCXXDeleteExpression(bool UseGlobal, SourceLocation Start) {
 
   // Array delete?
   bool ArrayDelete = false;
-  if (Tok.is(tok::l_square)) {
+  if (Tok.is(tok::l_square) && NextToken().is(tok::r_square)) {
+    // FIXME: This could be the start of a lambda-expression. We should
+    // disambiguate this, but that will require arbitrary lookahead if
+    // the next token is '(':
+    //   delete [](int*){ /* ... */
     ArrayDelete = true;
     BalancedDelimiterTracker T(*this, tok::l_square);