[libcxx] Mark most test/std/future tests as UNSUPPORTED in C++03

Summary:
This patch marks *most* tests for `std::promise`, `std::future` and `std::shared_future` as unsupported in C++03. These tests fail in C++03 mode because they attempt to copy a `std::future` even though it is a `MoveOnly` type. AFAIK the missing move-semantics in `std::future` is the only reason these tests fail but without move semantics these classes are useless. For example even though `std::promise::set_value` and `std::promise::set_exception(...)` work in C++03 `std::promise` is still useless because we cannot call `std::promise::get_future(...)`.

It might be possible to hack `std::move(...)` like we do for `std::unique_ptr` to make the move semantics work but I don't think it is worth the effort. Instead I think we should leave the `<future>` header as-is and mark the failing tests as `UNSUPPORTED`. I don't believe there are any users of `std::future` or `std::promise` in C++03 because they are so unusable. Therefore I am not concerned about losing test coverage and possibly breaking users. However because there are still parts of `<future>` that work in C++03 it would be wrong to `#ifdef` out the entire header.

@mclow.lists Should we take further steps to prevent the use of `std::promise`, `std::future` and `std::shared_future` in C++03?


Note: This patch also cleans up the tests and converts them to use `support/test_allocator.h` instead of a duplicate class in `test/std/futures/test_allocator.h`.

Reviewers: mclow.lists

Subscribers: vsk, mclow.lists, cfe-commits

Differential Revision: http://reviews.llvm.org/D12135

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@246271 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 16 deletions

diff --git a/test/std/thread/futures/futures.promise/move_ctor.pass.cpp b/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
index eeec4fb15..d45c48a95 100644
--- a/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
+++ b/test/std/thread/futures/futures.promise/move_ctor.pass.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 //
 // UNSUPPORTED: libcpp-has-no-threads
+// UNSUPPORTED: c++98, c++03
 
 // <future>
 
@@ -18,18 +19,17 @@
 #include <future>
 #include <cassert>
 
-#include "../test_allocator.h"
+#include "test_allocator.h"
 
 int main()
 {
-#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
-    assert(test_alloc_base::count == 0);
+    assert(test_alloc_base::alloc_count == 0);
     {
         std::promise<int> p0(std::allocator_arg, test_allocator<int>());
         std::promise<int> p(std::move(p0));
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         std::future<int> f = p.get_future();
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         assert(f.valid());
         try
         {
@@ -40,15 +40,15 @@ int main()
         {
             assert(e.code() == make_error_code(std::future_errc::no_state));
         }
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
     }
-    assert(test_alloc_base::count == 0);
+    assert(test_alloc_base::alloc_count == 0);
     {
         std::promise<int&> p0(std::allocator_arg, test_allocator<int>());
         std::promise<int&> p(std::move(p0));
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         std::future<int&> f = p.get_future();
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         assert(f.valid());
         try
         {
@@ -59,15 +59,15 @@ int main()
         {
             assert(e.code() == make_error_code(std::future_errc::no_state));
         }
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
     }
-    assert(test_alloc_base::count == 0);
+    assert(test_alloc_base::alloc_count == 0);
     {
         std::promise<void> p0(std::allocator_arg, test_allocator<void>());
         std::promise<void> p(std::move(p0));
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         std::future<void> f = p.get_future();
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
         assert(f.valid());
         try
         {
@@ -78,8 +78,7 @@ int main()
         {
             assert(e.code() == make_error_code(std::future_errc::no_state));
         }
-        assert(test_alloc_base::count == 1);
+        assert(test_alloc_base::alloc_count == 1);
     }
-    assert(test_alloc_base::count == 0);
-#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    assert(test_alloc_base::alloc_count == 0);
 }