Add support for "fancy" pointers to promise and packaged_task.

Summary:
This patch is very closely related to D4859. Please see http://reviews.llvm.org/D4859 for more information.

This patch adds support for "fancy" pointers and allocators to promise and packaged_task. The changes made to support this are exactly the same as in D4859.



Test Plan: "fancy" pointer tests were added to each constructor affected by the change.

Reviewers: danalbert, mclow.lists

Reviewed By: mclow.lists

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D4862

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@220471 91177308-0d34-0410-b5e6-96231b3b80d8

test/thread/futures/futures.promise/alloc_ctor.pass.cpp

@@ -20,6 +20,7 @@
 #include <cassert>
 
 #include "../test_allocator.h"
+#include "min_allocator.h"
 
 int main()
 {
@@ -48,4 +49,36 @@ int main()
         assert(f.valid());
     }
     assert(test_alloc_base::count == 0);
+    // Test with a minimal allocator
+    {
+        std::promise<int> p(std::allocator_arg, bare_allocator<void>());
+        std::future<int> f = p.get_future();
+        assert(f.valid());
+    }
+    {
+        std::promise<int&> p(std::allocator_arg, bare_allocator<void>());
+        std::future<int&> f = p.get_future();
+        assert(f.valid());
+    }
+    {
+        std::promise<void> p(std::allocator_arg, bare_allocator<void>());
+        std::future<void> f = p.get_future();
+        assert(f.valid());
+    }
+    // Test with a minimal allocator that returns class-type pointers
+    {
+        std::promise<int> p(std::allocator_arg, min_allocator<void>());
+        std::future<int> f = p.get_future();
+        assert(f.valid());
+    }
+    {
+        std::promise<int&> p(std::allocator_arg, min_allocator<void>());
+        std::future<int&> f = p.get_future();
+        assert(f.valid());
+    }
+    {
+        std::promise<void> p(std::allocator_arg, min_allocator<void>());
+        std::future<void> f = p.get_future();
+        assert(f.valid());
+    }
 }

test/thread/futures/futures.tas/futures.task.members/ctor_func_alloc.pass.cpp

@@ -20,6 +20,7 @@
 #include <cassert>
 
 #include "../../test_allocator.h"
+#include "min_allocator.h"
 
 class A
 {
@@ -94,4 +95,30 @@ int main()
         assert(f.get() == 4);
     }
     assert(test_alloc_base::count == 0);
+    A::n_copies = 0;
+    A::n_moves  = 0;
+    {
+        std::packaged_task<double(int, char)> p(std::allocator_arg,
+                                                bare_allocator<void>(), A(5));
+        assert(p.valid());
+        std::future<double> f = p.get_future();
+        p(3, 'a');
+        assert(f.get() == 105.0);
+        assert(A::n_copies == 0);
+        assert(A::n_moves > 0);
+    }
+    A::n_copies = 0;
+    A::n_moves  = 0;
+    {
+        std::packaged_task<double(int, char)> p(std::allocator_arg,
+                                                min_allocator<void>(), A(5));
+        assert(p.valid());
+        std::future<double> f = p.get_future();
+        p(3, 'a');
+        assert(f.get() == 105.0);
+        assert(A::n_copies == 0);
+        assert(A::n_moves > 0);
+    }
+    A::n_copies = 0;
+    A::n_moves  = 0;
 }