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

2 files changed, 33 insertions, 2 deletions

diff --git a/test/SemaCXX/new-delete-0x.cpp b/test/SemaCXX/new-delete-0x.cpp
new file mode 100644
index 0000000000..dcc2e9b8b1
--- /dev/null
+++ b/test/SemaCXX/new-delete-0x.cpp
@@ -0,0 +1,32 @@
+// RUN: %clang_cc1 -fsyntax-only -verify %s -triple=i686-pc-linux-gnu -std=c++11
+
+using size_t = decltype(sizeof(0));
+struct noreturn_t {} constexpr noreturn = {};
+
+void *operator new [[noreturn]] (size_t, noreturn_t);
+void operator delete [[noreturn]] (void*, noreturn_t);
+
+void good_news()
+{
+  auto p = new int[2][[]];
+  auto q = new int[[]][2];
+  auto r = new int*[[]][2][[]];
+  auto s = new (int(*[[]])[2][[]]);
+}
+
+void bad_news(int *ip)
+{
+  // attribute-specifiers can go almost anywhere in a new-type-id...
+  auto r = new int[[]{return 1;}()][2]; // expected-error {{expected ']'}}
+  auto s = new int*[[]{return 1;}()][2]; // expected-error {{expected ']'}}
+  // ... but not here:
+  auto t = new (int(*)[[]]); // expected-error {{an attribute list cannot appear here}}
+  auto u = new (int(*)[[]{return 1;}()][2]); // expected-error {{C++11 only allows consecutive left square brackets when introducing an attribute}} expected-error {{variably modified type}}
+}
+
+void good_deletes()
+{
+  delete [&]{ return (int*)0; }();
+  // FIXME: This appears to be legal.
+  delete []{ return (int*)0; }(); // unexpected-error {{expected expression}}
+}
diff --git a/test/SemaCXX/new-delete.cpp b/test/SemaCXX/new-delete.cpp
index 88d85ca792..e77e3d652f 100644
--- a/test/SemaCXX/new-delete.cpp
+++ b/test/SemaCXX/new-delete.cpp
@@ -102,8 +102,7 @@ void good_deletes()
 void bad_deletes()
 {
   delete 0; // expected-error {{cannot delete expression of type 'int'}}
-  delete [0] (int*)0; // expected-error {{expected ']'}} \
-                      // expected-note {{to match this '['}}
+  delete [0] (int*)0; // expected-error {{expected expression}}
   delete (void*)0; // expected-warning {{cannot delete expression with pointer-to-'void' type 'void *'}}
   delete (T*)0; // expected-warning {{deleting pointer to incomplete type}}
   ::S::delete (int*)0; // expected-error {{expected unqualified-id}}