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Re: [PATCH] libstdc++: Allow using <future> without lock free atomic int
- From: Jonathan Wakely <jwakely at redhat dot com>
- To: Pauli <suokkos at gmail dot com>
- Cc: libstdc++ at gcc dot gnu dot org, gcc-patches at gcc dot gnu dot org
- Date: Mon, 19 Dec 2016 17:52:27 +0000
- Subject: Re: [PATCH] libstdc++: Allow using <future> without lock free atomic int
- Authentication-results: sourceware.org; auth=none
- References: <20161109212623.2488-1-suokkos@gmail.com> <20161216175257.GG895@redhat.com>
On 16/12/16 17:52 +0000, Jonathan Wakely wrote:
On 09/11/16 23:26 +0200, Pauli wrote:
Compiling programs using std::future for old arm processors fails. The
problem is caused by preprocessor check for atomic lock free int.
Future can be changed to work correctly without lock free atomics with
minor changes to exception_ptr implementation.
Without lock free atomics there is question if deadlock can happen. But
atomic operations can't call outside code preventing any ABBA or
recursive mutex acquiring deadlocks.
Deadlock could happen if throwing an exception or access
is_lock_free() == false atomic from asynchronous signal handler.
Throwing from signal handler is undefined behavior. I don't know about
accessing atomics from asynchronous signal handler but that feels like
undefined behavior if is_lock_free returns false.
Bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64735
differences to current if atomic builtins available:
* Race detector annotations that are empty by default
* Check for __gthread_active_p
* Generate x86 code uses xadd instead of xsub
This makes code a bit worse. But problem is duplicated to any other user
of __exchange_and_add. The internal API implementation should be fixed
to generate better code for all cases. But that is a follow up patch.
I'd prefer to do it so we don't change anything for the targets that
already work. Your follow-up patch missed the deadline for GCC 7 and
so will have to wait for GCC 8 now, and we don't want to pessimize
x86.
Also, I think your patch actually breaks some GNU/Linux targets,
because you removed the <atomic_lockfree_defines.h> header from
<exception>, which means that in libsupc++/guard.cc the macro
ATOMIC_INT_LOCK_FREE is no longer defined, and so _GLIBCXX_USE_FUTEX
doesn't get defined. Now arguably guard.cc should have been including
the header directly, but it still shows why such an invasive patch is
a bad idea at this stage of the GCC 7 process.
The attached patch attempts to make exception propagation work for all
targets, without changing anything if it already works.
Do you see any problems with this alternative approach?
Could you please test it for armv5te?
It passes all tests for x86_64-linux and ppc64le-linux.
For your follow-up patch, do you already have a copyright assignment
for contributions to GCC? We'll probably need that before it can be
accepted. We don't need one for this patch, because what remains of
your original patch is just the testsuite changes, which are
mechanical and not copyrightable.
We also need to adjust the linker script to avoid adding new exports
to old symbol versions, revised patch attached. I think it would be
better to make configure define a macro like
HAVE_EXCEPTION_PTR_SINCE_GCC6 and use that in the linker script
instead of testing __GCC_ATOMIC_INT_LOCK_FREE directly. I'll work on
that.
commit a19855aecf301a30bb1d6f6c39fe2a458baddd48
Author: Jonathan Wakely <jwakely@redhat.com>
Date: Fri Dec 16 15:22:21 2016 +0000
PR64735 support exception propagation without atomics
2016-12-19 Pauli Nieminen <suokkos@gmail.com>
Jonathan Wakely <jwakely@redhat.com>
PR libstdc++/64735
* config/abi/pre/gnu.ver [__GCC_ATOMIC_INT_LOCK_FREE > 1]
(GLIBCXX_3.4.15, GLIBCXX_3.4.21, CXXABI_1.3.3, CXXABI_1.3.5): Make
exports for exception_ptr, nested_exception, and future conditional.
[__GCC_ATOMIC_INT_LOCK_FREE <= 1] (GLIBCXX_3.4.23, CXXABI_1.3.11): Add
exports for exception_ptr, nested_exception, and future conditional.
* include/std/future: Remove check for ATOMIC_INT_LOCK_FREE
* libsupc++/eh_atomics.h: New file for internal use only.
(__eh_atomic_inc, __eh_atomic_dec): New.
* libsupc++/eh_ptr.cc (exception_ptr::_M_addref)
(exception_ptr::_M_release) (__gxx_dependent_exception_cleanup)
(rethrow_exception): Use eh_atomics.h reference counting helpers.
* libsupc++/eh_throw.cc (__gxx_exception_cleanup): Likewise.
* libsupc++/eh_tm.cc (free_any_cxa_exception): Likewise.
* libsupc++/exception: Remove check for ATOMIC_INT_LOCK_FREE.
* libsupc++/exception_ptr.h: Likewise.
* libsupc++/guard.cc: Include header for ATOMIC_INT_LOCK_FREE macro.
* libsupc++/nested_exception.cc: Remove check for
ATOMIC_INT_LOCK_FREE.
* libsupc++/nested_exception.h: Likewise.
* src/c++11/future.cc: Likewise.
* testsuite/18_support/exception_ptr/*: Remove atomic builtins checks.
* testsuite/18_support/nested_exception/*: Likewise.
* testsuite/30_threads/async/*: Likewise.
* testsuite/30_threads/future/*: Likewise.
* testsuite/30_threads/headers/future/types_std_c++0x.cc: Likewise.
* testsuite/30_threads/packaged_task/*: Likewise.
* testsuite/30_threads/promise/*: Likewise.
* testsuite/30_threads/shared_future/*: Likewise.
diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver
index 8b0f67b..5da698e 100644
--- a/libstdc++-v3/config/abi/pre/gnu.ver
+++ b/libstdc++-v3/config/abi/pre/gnu.ver
@@ -1503,6 +1503,9 @@ GLIBCXX_3.4.15 {
_ZNSt14error_categoryC*;
_ZNSt14error_categoryD*;
+#if __GCC_ATOMIC_INT_LOCK_FREE > 1
+ # std::future symbols are only present in this version when
+ # atomic operations on int are always lock-free.
_ZNSt13__future_base12_Result_baseC*;
_ZNSt13__future_base12_Result_baseD*;
_ZTINSt13__future_base12_Result_baseE;
@@ -1511,6 +1514,7 @@ GLIBCXX_3.4.15 {
_ZNSt13__future_base11_State_baseD*;
_ZTINSt13__future_base11_State_baseE;
_ZTVNSt13__future_base11_State_baseE;
+#endif
} GLIBCXX_3.4.14;
@@ -1687,8 +1691,10 @@ GLIBCXX_3.4.21 {
# std::notify_all_at_thread_exit
_ZSt25notify_all_at_thread_exitRSt18condition_variableSt11unique_lockISt5mutexE;
+#if __GCC_ATOMIC_INT_LOCK_FREE > 1
# std::__future_base::_State_baseV2::_Make_ready::_M_set()
_ZNSt13__future_base13_State_baseV211_Make_ready6_M_setEv;
+#endif
# ABI-tagged std::basic_string
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE1[01]**;
@@ -1947,6 +1953,16 @@ GLIBCXX_3.4.23 {
_ZNSsC[12]ERKSs[jmy]RKSaIcE;
_ZNSbIwSt11char_traitsIwESaIwEEC[12]ERKS2_mRKS1_;
+#if __GCC_ATOMIC_INT_LOCK_FREE <= 1
+ # std::future symbols were first exported for this version
+ # when atomic operations on int are not always lock-free.
+ _ZNSt13__future_base12_Result_baseC*;
+ _ZNSt13__future_base12_Result_baseD*;
+ _ZTINSt13__future_base12_Result_baseE;
+ _ZTVNSt13__future_base12_Result_baseE;
+ _ZNSt13__future_base13_State_baseV211_Make_ready6_M_setEv;
+#endif
+
} GLIBCXX_3.4.22;
# Symbols in the support library (libsupc++) have their own tag.
@@ -2080,6 +2096,7 @@ CXXABI_1.3.3 {
_ZTIPDi;
_ZTIPKDi;
+#if __GCC_ATOMIC_INT_LOCK_FREE > 1
# exception_ptr
_ZNSt15__exception_ptr13exception_ptrC1Ev;
_ZNSt15__exception_ptr13exception_ptrC2Ev;
@@ -2099,6 +2116,7 @@ CXXABI_1.3.3 {
_ZSt17current_exceptionv;
_ZSt17rethrow_exceptionNSt15__exception_ptr13exception_ptrE;
+#endif
} CXXABI_1.3.2;
@@ -2129,10 +2147,12 @@ CXXABI_1.3.5 {
# FNV hash.
_ZSt15_Fnv_hash_bytesPKv*;
+#if __GCC_ATOMIC_INT_LOCK_FREE > 1
# std::nested_exception
_ZNSt16nested_exceptionD*;
_ZTISt16nested_exception;
_ZTVSt16nested_exception;
+#endif
} CXXABI_1.3.4;
@@ -2209,6 +2229,33 @@ CXXABI_1.3.11 {
_ZdaPvSt11align_val_tRKSt9nothrow_t;
_ZdaPv[jmy]St11align_val_t;
+#if __GCC_ATOMIC_INT_LOCK_FREE <= 1
+ # exception_ptr
+ _ZNSt15__exception_ptr13exception_ptrC1Ev;
+ _ZNSt15__exception_ptr13exception_ptrC2Ev;
+ _ZNSt15__exception_ptr13exception_ptrC1ERKS0_;
+ _ZNSt15__exception_ptr13exception_ptrC2ERKS0_;
+ _ZNSt15__exception_ptr13exception_ptrC1EMS0_FvvE;
+ _ZNSt15__exception_ptr13exception_ptrC2EMS0_FvvE;
+ _ZNSt15__exception_ptr13exception_ptrD1Ev;
+ _ZNSt15__exception_ptr13exception_ptrD2Ev;
+ _ZNSt15__exception_ptr13exception_ptraSERKS0_;
+ _ZNKSt15__exception_ptr13exception_ptrcvMS0_FvvEEv;
+ _ZNKSt15__exception_ptr13exception_ptrntEv;
+ _ZNKSt15__exception_ptr13exception_ptr20__cxa_exception_typeEv;
+ _ZNSt15__exception_ptr13exception_ptr4swapERS0_;
+ _ZNSt15__exception_ptreqERKNS_13exception_ptrES2_;
+ _ZNSt15__exception_ptrneERKNS_13exception_ptrES2_;
+
+ _ZSt17current_exceptionv;
+ _ZSt17rethrow_exceptionNSt15__exception_ptr13exception_ptrE;
+
+ # std::nested_exception
+ _ZNSt16nested_exceptionD*;
+ _ZTISt16nested_exception;
+ _ZTVSt16nested_exception;
+#endif
+
} CXXABI_1.3.10;
# Symbols in the support library (libsupc++) supporting transactional memory.
diff --git a/libstdc++-v3/include/std/future b/libstdc++-v3/include/std/future
index 8ba1306..b83d74b 100644
--- a/libstdc++-v3/include/std/future
+++ b/libstdc++-v3/include/std/future
@@ -192,8 +192,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
future<__async_result_of<_Fn, _Args...>>
async(_Fn&& __fn, _Args&&... __args);
-#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) \
- && (ATOMIC_INT_LOCK_FREE > 1)
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
/// Base class and enclosing scope.
struct __future_base
@@ -1751,7 +1750,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
#endif // _GLIBCXX_ASYNC_ABI_COMPAT
#endif // _GLIBCXX_HAS_GTHREADS && _GLIBCXX_USE_C99_STDINT_TR1
- // && ATOMIC_INT_LOCK_FREE
// @} group futures
_GLIBCXX_END_NAMESPACE_VERSION
diff --git a/libstdc++-v3/libsupc++/eh_atomics.h b/libstdc++-v3/libsupc++/eh_atomics.h
new file mode 100644
index 0000000..71b42a4
--- /dev/null
+++ b/libstdc++-v3/libsupc++/eh_atomics.h
@@ -0,0 +1,84 @@
+// Exception Handling support header for -*- C++ -*-
+
+// Copyright (C) 2016 Free Software Foundation, Inc.
+//
+// This file is part of GCC.
+//
+// GCC is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3, or (at your option)
+// any later version.
+//
+// GCC is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+/** @file eh_atomics.h
+ * This is an internal header file, included by library source files.
+ * Do not attempt to use it directly.
+ */
+
+#ifndef _EH_ATOMICS_H
+#define _EH_ATOMICS_H 1
+
+#include <bits/c++config.h>
+#include <bits/atomic_word.h>
+#include <bits/atomic_lockfree_defines.h>
+#if ATOMIC_INT_LOCK_FREE <= 1
+# include <ext/atomicity.h>
+#endif
+
+#pragma GCC visibility push(default)
+extern "C++" {
+namespace __gnu_cxx
+{
+ void
+ __eh_atomic_inc (_Atomic_word* __count) __attribute__((always_inline));
+
+ bool
+ __eh_atomic_dec (_Atomic_word* __count) __attribute__((always_inline));
+
+ // Increments the count.
+ inline void
+ __eh_atomic_inc (_Atomic_word* __count)
+ {
+#if ATOMIC_INT_LOCK_FREE > 1
+ __atomic_add_fetch (__count, 1, __ATOMIC_ACQ_REL);
+#else
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE (__count);
+ __gnu_cxx::__atomic_add_dispatch (__count, 1);
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER (__count);
+#endif
+ }
+
+ // Decrements the count and returns true if it reached zero.
+ inline bool
+ __eh_atomic_dec (_Atomic_word* __count)
+ {
+#if ATOMIC_INT_LOCK_FREE > 1
+ return __atomic_sub_fetch (__count, 1, __ATOMIC_ACQ_REL) == 0;
+#else
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE (__count);
+ if (__gnu_cxx::__exchange_and_add_dispatch (__count, -1) == 1)
+ {
+ _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER (__count);
+ return true;
+ }
+ return false;
+#endif
+ }
+} // namespace __gnu_cxx
+}
+#pragma GCC visibility pop
+
+#endif // _EH_ATOMICS_H
diff --git a/libstdc++-v3/libsupc++/eh_ptr.cc b/libstdc++-v3/libsupc++/eh_ptr.cc
index f3c910b..33e3a21 100644
--- a/libstdc++-v3/libsupc++/eh_ptr.cc
+++ b/libstdc++-v3/libsupc++/eh_ptr.cc
@@ -23,9 +23,7 @@
// <http://www.gnu.org/licenses/>.
#include <bits/c++config.h>
-#include <bits/atomic_lockfree_defines.h>
-
-#if ATOMIC_INT_LOCK_FREE > 1
+#include "eh_atomics.h"
#define _GLIBCXX_EH_PTR_COMPAT
@@ -101,7 +99,7 @@ std::__exception_ptr::exception_ptr::_M_addref() noexcept
{
__cxa_refcounted_exception *eh =
__get_refcounted_exception_header_from_obj (_M_exception_object);
- __atomic_add_fetch (&eh->referenceCount, 1, __ATOMIC_ACQ_REL);
+ __gnu_cxx::__eh_atomic_inc (&eh->referenceCount);
}
}
@@ -113,7 +111,7 @@ std::__exception_ptr::exception_ptr::_M_release() noexcept
{
__cxa_refcounted_exception *eh =
__get_refcounted_exception_header_from_obj (_M_exception_object);
- if (__atomic_sub_fetch (&eh->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
+ if (__gnu_cxx::__eh_atomic_dec (&eh->referenceCount))
{
if (eh->exc.exceptionDestructor)
eh->exc.exceptionDestructor (_M_exception_object);
@@ -211,7 +209,7 @@ __gxx_dependent_exception_cleanup(_Unwind_Reason_Code code,
__cxa_free_dependent_exception (dep);
- if (__atomic_sub_fetch (&header->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
+ if (__gnu_cxx::__eh_atomic_dec (&header->referenceCount))
{
if (header->exc.exceptionDestructor)
header->exc.exceptionDestructor (header + 1);
@@ -230,7 +228,7 @@ std::rethrow_exception(std::exception_ptr ep)
__cxa_dependent_exception *dep = __cxa_allocate_dependent_exception ();
dep->primaryException = obj;
- __atomic_add_fetch (&eh->referenceCount, 1, __ATOMIC_ACQ_REL);
+ __gnu_cxx::__eh_atomic_inc (&eh->referenceCount);
dep->unexpectedHandler = get_unexpected ();
dep->terminateHandler = get_terminate ();
@@ -252,5 +250,3 @@ std::rethrow_exception(std::exception_ptr ep)
}
#undef _GLIBCXX_EH_PTR_COMPAT
-
-#endif
diff --git a/libstdc++-v3/libsupc++/eh_throw.cc b/libstdc++-v3/libsupc++/eh_throw.cc
index a05f4eb..0174a93 100644
--- a/libstdc++-v3/libsupc++/eh_throw.cc
+++ b/libstdc++-v3/libsupc++/eh_throw.cc
@@ -24,6 +24,7 @@
#include <bits/c++config.h>
#include "unwind-cxx.h"
+#include "eh_atomics.h"
using namespace __cxxabiv1;
@@ -42,17 +43,13 @@ __gxx_exception_cleanup (_Unwind_Reason_Code code, _Unwind_Exception *exc)
if (code != _URC_FOREIGN_EXCEPTION_CAUGHT && code != _URC_NO_REASON)
__terminate (header->exc.terminateHandler);
-#if ATOMIC_INT_LOCK_FREE > 1
- if (__atomic_sub_fetch (&header->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
+ if (__gnu_cxx::__eh_atomic_dec (&header->referenceCount))
{
-#endif
if (header->exc.exceptionDestructor)
header->exc.exceptionDestructor (header + 1);
__cxa_free_exception (header + 1);
-#if ATOMIC_INT_LOCK_FREE > 1
}
-#endif
}
extern "C" __cxa_refcounted_exception*
diff --git a/libstdc++-v3/libsupc++/eh_tm.cc b/libstdc++-v3/libsupc++/eh_tm.cc
index c05f611..85ae46c 100644
--- a/libstdc++-v3/libsupc++/eh_tm.cc
+++ b/libstdc++-v3/libsupc++/eh_tm.cc
@@ -24,6 +24,7 @@
#include <cstdlib>
#include "unwind-cxx.h"
+#include "eh_atomics.h"
using namespace __cxxabiv1;
@@ -45,9 +46,7 @@ free_any_cxa_exception (_Unwind_Exception *eo)
__cxa_free_dependent_exception (dep);
}
-#if __GCC_ATOMIC_INT_LOCK_FREE > 1
- if (__atomic_sub_fetch (&h->referenceCount, 1, __ATOMIC_ACQ_REL) == 0)
-#endif
+ if (__gnu_cxx::__eh_atomic_dec (&h->referenceCount))
__cxa_free_exception (h + 1);
}
diff --git a/libstdc++-v3/libsupc++/exception b/libstdc++-v3/libsupc++/exception
index 8be903b..021d70e 100644
--- a/libstdc++-v3/libsupc++/exception
+++ b/libstdc++-v3/libsupc++/exception
@@ -35,7 +35,6 @@
#pragma GCC visibility push(default)
#include <bits/c++config.h>
-#include <bits/atomic_lockfree_defines.h>
#include <bits/exception.h>
extern "C++" {
@@ -139,7 +138,7 @@ _GLIBCXX_END_NAMESPACE_VERSION
#pragma GCC visibility pop
-#if (__cplusplus >= 201103L) && (ATOMIC_INT_LOCK_FREE > 1)
+#if (__cplusplus >= 201103L)
#include <bits/exception_ptr.h>
#include <bits/nested_exception.h>
#endif
diff --git a/libstdc++-v3/libsupc++/exception_ptr.h b/libstdc++-v3/libsupc++/exception_ptr.h
index a47a585..cce156a 100644
--- a/libstdc++-v3/libsupc++/exception_ptr.h
+++ b/libstdc++-v3/libsupc++/exception_ptr.h
@@ -39,10 +39,6 @@
#include <typeinfo>
#include <new>
-#if ATOMIC_INT_LOCK_FREE < 2
-# error This platform does not support exception propagation.
-#endif
-
extern "C++" {
namespace std
diff --git a/libstdc++-v3/libsupc++/guard.cc b/libstdc++-v3/libsupc++/guard.cc
index 9b61799..66edffb 100644
--- a/libstdc++-v3/libsupc++/guard.cc
+++ b/libstdc++-v3/libsupc++/guard.cc
@@ -30,6 +30,7 @@
#include <new>
#include <ext/atomicity.h>
#include <ext/concurrence.h>
+#include <bits/atomic_lockfree_defines.h>
#if defined(__GTHREADS) && defined(__GTHREAD_HAS_COND) \
&& (ATOMIC_INT_LOCK_FREE > 1) && defined(_GLIBCXX_HAVE_LINUX_FUTEX)
# include <climits>
diff --git a/libstdc++-v3/libsupc++/nested_exception.cc b/libstdc++-v3/libsupc++/nested_exception.cc
index c1a7b7a..82dddb1 100644
--- a/libstdc++-v3/libsupc++/nested_exception.cc
+++ b/libstdc++-v3/libsupc++/nested_exception.cc
@@ -25,7 +25,5 @@
namespace std
{
-#if ATOMIC_INT_LOCK_FREE > 1
nested_exception::~nested_exception() noexcept = default;
-#endif
} // namespace std
diff --git a/libstdc++-v3/libsupc++/nested_exception.h b/libstdc++-v3/libsupc++/nested_exception.h
index 078af0e..48bdabb 100644
--- a/libstdc++-v3/libsupc++/nested_exception.h
+++ b/libstdc++-v3/libsupc++/nested_exception.h
@@ -39,10 +39,6 @@
#include <bits/c++config.h>
#include <bits/move.h>
-#if ATOMIC_INT_LOCK_FREE < 2
-# error This platform does not support exception propagation.
-#endif
-
extern "C++" {
namespace std
diff --git a/libstdc++-v3/src/c++11/future.cc b/libstdc++-v3/src/c++11/future.cc
index 7809a37..a14051a 100644
--- a/libstdc++-v3/src/c++11/future.cc
+++ b/libstdc++-v3/src/c++11/future.cc
@@ -78,8 +78,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
const char*
future_error::what() const noexcept { return logic_error::what(); }
-#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) \
- && (ATOMIC_INT_LOCK_FREE > 1)
+#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
__future_base::_Result_base::_Result_base() = default;
__future_base::_Result_base::~_Result_base() = default;
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/40296.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/40296.cc
index 74307cc..a6659b8 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/40296.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/40296.cc
@@ -1,5 +1,4 @@
// { dg-do compile { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/60612-terminate.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/60612-terminate.cc
index c00e287..d58f32d 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/60612-terminate.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/60612-terminate.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/60612-unexpected.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/60612-unexpected.cc
index 2b5ec2d..cfaea5d4 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/60612-unexpected.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/60612-unexpected.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/62258.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/62258.cc
index c83d5fb..5c15b48 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/62258.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/62258.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2015-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/64241.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/64241.cc
index c1e9a05..7dbf3d6 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/64241.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/64241.cc
@@ -17,7 +17,6 @@
// { dg-options "-fno-exceptions -O0" }
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
#include <exception>
#include <testsuite_hooks.h>
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/current_exception.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/current_exception.cc
index 79459eb..38decc1 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/current_exception.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/current_exception.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// 2008-05-25 Sebastian Redl <sebastian.redl@getdesigned.at>
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/lifespan.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/lifespan.cc
index ada652e..8343b49 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/lifespan.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/lifespan.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// 2008-05-25 Sebastian Redl <sebastian.redl@getdesigned.at>
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr.cc
index b9ded35..c35525e 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr_2.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr_2.cc
index 3787777..ad0333b 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr_2.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/make_exception_ptr_2.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/move.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/move.cc
index 6318bc4..80c6e3e 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/move.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/move.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/requirements.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/requirements.cc
index b3b9e0c..5f5f054 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/requirements.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/requirements.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/requirements_neg.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/requirements_neg.cc
index b80d688..95ec8ab 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/requirements_neg.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/requirements_neg.cc
@@ -1,5 +1,4 @@
// { dg-do compile { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/exception_ptr/rethrow_exception.cc b/libstdc++-v3/testsuite/18_support/exception_ptr/rethrow_exception.cc
index 567af32..7f2ab93 100644
--- a/libstdc++-v3/testsuite/18_support/exception_ptr/rethrow_exception.cc
+++ b/libstdc++-v3/testsuite/18_support/exception_ptr/rethrow_exception.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// 2008-05-25 Sebastian Redl <sebastian.redl@getdesigned.at>
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/51438.cc b/libstdc++-v3/testsuite/18_support/nested_exception/51438.cc
index 04ef32f..34728043 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/51438.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/51438.cc
@@ -1,5 +1,4 @@
// { dg-do compile { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc b/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
index f1884a5..124e4d1 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/62154.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/68139.cc b/libstdc++-v3/testsuite/18_support/nested_exception/68139.cc
index bf803db..4164e91 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/68139.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/68139.cc
@@ -1,5 +1,4 @@
// { dg-do compile { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2015-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/cons.cc b/libstdc++-v3/testsuite/18_support/nested_exception/cons.cc
index af6f90c..a1141b7 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/cons.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/cons.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/nested_ptr.cc b/libstdc++-v3/testsuite/18_support/nested_exception/nested_ptr.cc
index 467d371..c9092bd 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/nested_ptr.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/nested_ptr.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_if_nested.cc b/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_if_nested.cc
index b042084..62dd26a 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_if_nested.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_if_nested.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_nested.cc b/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_nested.cc
index fd374e5..c18f6f0 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_nested.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/rethrow_nested.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/18_support/nested_exception/throw_with_nested.cc b/libstdc++-v3/testsuite/18_support/nested_exception/throw_with_nested.cc
index f768b1e..3036328 100644
--- a/libstdc++-v3/testsuite/18_support/nested_exception/throw_with_nested.cc
+++ b/libstdc++-v3/testsuite/18_support/nested_exception/throw_with_nested.cc
@@ -1,5 +1,4 @@
// { dg-do run { target c++11 } }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/42819.cc b/libstdc++-v3/testsuite/30_threads/async/42819.cc
index b836877..44cb674 100644
--- a/libstdc++-v3/testsuite/30_threads/async/42819.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/42819.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/49668.cc b/libstdc++-v3/testsuite/30_threads/async/49668.cc
index fe597c0..074d9b0 100644
--- a/libstdc++-v3/testsuite/30_threads/async/49668.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/49668.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/54297.cc b/libstdc++-v3/testsuite/30_threads/async/54297.cc
index 756fd97..ed9230d 100644
--- a/libstdc++-v3/testsuite/30_threads/async/54297.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/54297.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// { dg-require-sleep "" }
// Copyright (C) 2012-2016 Free Software Foundation, Inc.
diff --git a/libstdc++-v3/testsuite/30_threads/async/any.cc b/libstdc++-v3/testsuite/30_threads/async/any.cc
index a78b0e5..03c6401 100644
--- a/libstdc++-v3/testsuite/30_threads/async/any.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/any.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/async.cc b/libstdc++-v3/testsuite/30_threads/async/async.cc
index 02c497c..3de9ef6 100644
--- a/libstdc++-v3/testsuite/30_threads/async/async.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/async.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/except.cc b/libstdc++-v3/testsuite/30_threads/async/except.cc
index 1a63680..0d94916 100644
--- a/libstdc++-v3/testsuite/30_threads/async/except.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/except.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/forced_unwind.cc b/libstdc++-v3/testsuite/30_threads/async/forced_unwind.cc
index b344b74..c44fd29 100644
--- a/libstdc++-v3/testsuite/30_threads/async/forced_unwind.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/forced_unwind.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/launch.cc b/libstdc++-v3/testsuite/30_threads/async/launch.cc
index 7064c91..6ea6834 100644
--- a/libstdc++-v3/testsuite/30_threads/async/launch.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/launch.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/async/lwg2021.cc b/libstdc++-v3/testsuite/30_threads/async/lwg2021.cc
index 62fbf27..3a631e9 100644
--- a/libstdc++-v3/testsuite/30_threads/async/lwg2021.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/lwg2021.cc
@@ -20,7 +20,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// LWG 2021. Further incorrect usages of result_of
// Arguments to result_of should use decay.
diff --git a/libstdc++-v3/testsuite/30_threads/async/sync.cc b/libstdc++-v3/testsuite/30_threads/async/sync.cc
index b4d47597..7fa11c8 100644
--- a/libstdc++-v3/testsuite/30_threads/async/sync.cc
+++ b/libstdc++-v3/testsuite/30_threads/async/sync.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
index a36dafb..467e7f0 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/assign_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/constexpr.cc b/libstdc++-v3/testsuite/30_threads/future/cons/constexpr.cc
index dcafe3e..b61ca13 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/constexpr.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/constexpr.cc
@@ -2,7 +2,6 @@
// { dg-options "-fno-inline -g0" }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// { dg-final { scan-assembler-not "_ZNSt6futureIvEC2Ev" } }
// { dg-final { scan-assembler-not "_ZNSt6futureIiEC2Ev" } }
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
index 8fc5de6..f53056d 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/copy_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/default.cc b/libstdc++-v3/testsuite/30_threads/future/cons/default.cc
index b9424be..13c6e01 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/default.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/default.cc
@@ -1,7 +1,6 @@
// { dg-do run { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/move.cc b/libstdc++-v3/testsuite/30_threads/future/cons/move.cc
index 63b017f..33d0b60 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/move.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/move.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/cons/move_assign.cc b/libstdc++-v3/testsuite/30_threads/future/cons/move_assign.cc
index 50971f3..910fe8e 100644
--- a/libstdc++-v3/testsuite/30_threads/future/cons/move_assign.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/cons/move_assign.cc
@@ -1,7 +1,6 @@
// { dg-do run { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/45133.cc b/libstdc++-v3/testsuite/30_threads/future/members/45133.cc
index 1f91483..e5d63bd 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/45133.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/45133.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/get.cc b/libstdc++-v3/testsuite/30_threads/future/members/get.cc
index b99837e..849c94a 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/get.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/get.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/get2.cc b/libstdc++-v3/testsuite/30_threads/future/members/get2.cc
index 6a259e7..60bcb42 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/get2.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/get2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/share.cc b/libstdc++-v3/testsuite/30_threads/future/members/share.cc
index cb163e2..1933725 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/share.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/share.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/valid.cc b/libstdc++-v3/testsuite/30_threads/future/members/valid.cc
index e473dc1..5993a97 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/valid.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/valid.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/wait.cc b/libstdc++-v3/testsuite/30_threads/future/members/wait.cc
index 6d08243..6553890 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/wait.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/wait.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/wait_for.cc b/libstdc++-v3/testsuite/30_threads/future/members/wait_for.cc
index 1b8707d..457de4d 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/wait_for.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/wait_for.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/members/wait_until.cc b/libstdc++-v3/testsuite/30_threads/future/members/wait_until.cc
index ed71c50..0b54b8a 100644
--- a/libstdc++-v3/testsuite/30_threads/future/members/wait_until.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/members/wait_until.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/future/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/30_threads/future/requirements/explicit_instantiation.cc
index 87d423f..592f03b 100644
--- a/libstdc++-v3/testsuite/30_threads/future/requirements/explicit_instantiation.cc
+++ b/libstdc++-v3/testsuite/30_threads/future/requirements/explicit_instantiation.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/headers/future/types_std_c++0x.cc b/libstdc++-v3/testsuite/30_threads/headers/future/types_std_c++0x.cc
index 3f9d273..c8f4e53 100644
--- a/libstdc++-v3/testsuite/30_threads/headers/future/types_std_c++0x.cc
+++ b/libstdc++-v3/testsuite/30_threads/headers/future/types_std_c++0x.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/49668.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/49668.cc
index 1ab9d19..cb74ab8 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/49668.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/49668.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/60564.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/60564.cc
index f2f4ce9..d5c940b 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/60564.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/60564.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/1.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/1.cc
index ce8d6c1..2297d7dc 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/1.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/1.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/2.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/2.cc
index f267192..655aa40 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/2.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/3.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/3.cc
index 6903778..97d7d86 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/3.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/3.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/56492.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/56492.cc
index 718608e..b96ceb0 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/56492.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/56492.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2013-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc.cc
index c0830e3..7b7099d 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc2.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc2.cc
index ebfc00a..726f50a 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc2.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc2.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc_min.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc_min.cc
index e67f9fd..96f6631 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc_min.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/alloc_min.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
index 1c88262..4b9cbb5 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/assign_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
index 7f1156f..05de5c6 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/copy_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move.cc
index 1fa2d77..f654647 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move_assign.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move_assign.cc
index 2ee5018..377b29f 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move_assign.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/cons/move_assign.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/forced_unwind.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/forced_unwind.cc
index 9059542..3c621d1 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/forced_unwind.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/forced_unwind.cc
@@ -1,7 +1,6 @@
// { dg-do run { target *-*-linux* *-*-gnu* } }
// { dg-options "-pthread" { target *-*-linux* *-*-gnu* *-*-solaris* } }
// { dg-require-effective-target c++11 }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/at_thread_exit.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/at_thread_exit.cc
index 72d1e66..5f0c7cd 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/at_thread_exit.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/at_thread_exit.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future.cc
index 85bbf5b..c7de321 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future2.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future2.cc
index 0ffd746..7b9d259 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future2.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/get_future2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke.cc
index fe4778a..5e09ef7 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke2.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke2.cc
index 27662d9..7790729 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke2.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke3.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke3.cc
index c3f5cec..411dd87 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke3.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke3.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke4.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke4.cc
index fb95c00..0fa2d09 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke4.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke4.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke5.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke5.cc
index 61fcb4a..fc7a33d 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke5.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/invoke5.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset.cc
index 1581b54..6aabe0d 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset2.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset2.cc
index 7581e36..dcdff24 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset2.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/reset2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/swap.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/swap.cc
index fa50b1d..466dfaa 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/swap.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/swap.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/members/valid.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/members/valid.cc
index 9b26152..1ee8c27 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/members/valid.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/members/valid.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/requirements/explicit_instantiation.cc
index e3b61e4..05a8518 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/requirements/explicit_instantiation.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/requirements/explicit_instantiation.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/packaged_task/uses_allocator.cc b/libstdc++-v3/testsuite/30_threads/packaged_task/uses_allocator.cc
index 1e2e9e0..fcee8c5 100644
--- a/libstdc++-v3/testsuite/30_threads/packaged_task/uses_allocator.cc
+++ b/libstdc++-v3/testsuite/30_threads/packaged_task/uses_allocator.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/60966.cc b/libstdc++-v3/testsuite/30_threads/promise/60966.cc
index 4030ff8..238dae5 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/60966.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/60966.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/69106.cc b/libstdc++-v3/testsuite/30_threads/promise/69106.cc
index 322a2f4..7201a94 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/69106.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/69106.cc
@@ -18,7 +18,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
#include <future>
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/1.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/1.cc
index 2ca2a9e..54d1bda 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/1.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/1.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc.cc
index d23ee29..5012026 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc2.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc2.cc
index e7567af..eb51229 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc2.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc2.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc_min.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc_min.cc
index bdac11e..30d1be4 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/alloc_min.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/alloc_min.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
index 4cbef6d..caa59a5 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/assign_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
index e66d047..f33673b 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/copy_neg.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/move.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/move.cc
index 5518840..93a97d1 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/move.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/move.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/cons/move_assign.cc b/libstdc++-v3/testsuite/30_threads/promise/cons/move_assign.cc
index 61ba488..2ec4c63 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/cons/move_assign.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/cons/move_assign.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/at_thread_exit.cc b/libstdc++-v3/testsuite/30_threads/promise/members/at_thread_exit.cc
index 5e8d9f3..3f1a40b 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/at_thread_exit.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/at_thread_exit.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2014-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/get_future.cc b/libstdc++-v3/testsuite/30_threads/promise/members/get_future.cc
index 209f545..0a2601d 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/get_future.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/get_future.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/get_future2.cc b/libstdc++-v3/testsuite/30_threads/promise/members/get_future2.cc
index 931da71..c5c14da 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/get_future2.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/get_future2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/set_exception.cc b/libstdc++-v3/testsuite/30_threads/promise/members/set_exception.cc
index 3672d18..cb3d003 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/set_exception.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/set_exception.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/set_exception2.cc b/libstdc++-v3/testsuite/30_threads/promise/members/set_exception2.cc
index e15d912..de725ef 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/set_exception2.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/set_exception2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/set_value.cc b/libstdc++-v3/testsuite/30_threads/promise/members/set_value.cc
index e3b7301..999ee31 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/set_value.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/set_value.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/set_value2.cc b/libstdc++-v3/testsuite/30_threads/promise/members/set_value2.cc
index bb26948..f63c847 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/set_value2.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/set_value2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/set_value3.cc b/libstdc++-v3/testsuite/30_threads/promise/members/set_value3.cc
index 1fa9d53..03c9aa2 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/set_value3.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/set_value3.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/members/swap.cc b/libstdc++-v3/testsuite/30_threads/promise/members/swap.cc
index b445d74..d718db9 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/members/swap.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/members/swap.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/30_threads/promise/requirements/explicit_instantiation.cc
index 4a220a9..6b73bd9 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/requirements/explicit_instantiation.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/requirements/explicit_instantiation.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/promise/uses_allocator.cc b/libstdc++-v3/testsuite/30_threads/promise/uses_allocator.cc
index e19a891..9d10067 100644
--- a/libstdc++-v3/testsuite/30_threads/promise/uses_allocator.cc
+++ b/libstdc++-v3/testsuite/30_threads/promise/uses_allocator.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2011-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/assign.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/assign.cc
index 572c658..c8b0532 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/assign.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/assign.cc
@@ -1,7 +1,6 @@
// { dg-do run { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/constexpr.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/constexpr.cc
index d0a5fe2..98b5098 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/constexpr.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/constexpr.cc
@@ -2,7 +2,6 @@
// { dg-options "-fno-inline -g0" }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// { dg-final { scan-assembler-not "_ZNSt13shared_futureIvEC2Ev" } }
// { dg-final { scan-assembler-not "_ZNSt13shared_futureIiEC2Ev" } }
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/copy.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/copy.cc
index 4628858..40eed23 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/copy.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/copy.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/default.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/default.cc
index ba96ab3..567b2ec 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/default.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/default.cc
@@ -1,7 +1,6 @@
// { dg-do run { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/move.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/move.cc
index 3d2666c..0484053 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/move.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/move.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/cons/move_assign.cc b/libstdc++-v3/testsuite/30_threads/shared_future/cons/move_assign.cc
index ae20b01..a6debee 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/cons/move_assign.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/cons/move_assign.cc
@@ -1,7 +1,6 @@
// { dg-do run { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/45133.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/45133.cc
index 4548fcc..6b2bc3c 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/45133.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/45133.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/get.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/get.cc
index efb84df..f9447f6 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/get.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/get.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/get2.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/get2.cc
index 20db446..3a237d7 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/get2.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/get2.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/valid.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/valid.cc
index 747456c..5238821 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/valid.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/valid.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2010-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait.cc
index bf925f1..52058c8 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_for.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_for.cc
index 714c4d2..d38fe07 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_for.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_for.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_until.cc b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_until.cc
index e99979a..2f70874 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_until.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/members/wait_until.cc
@@ -3,7 +3,6 @@
// { dg-require-effective-target c++11 }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//
diff --git a/libstdc++-v3/testsuite/30_threads/shared_future/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/30_threads/shared_future/requirements/explicit_instantiation.cc
index 715b7fe..49fc122 100644
--- a/libstdc++-v3/testsuite/30_threads/shared_future/requirements/explicit_instantiation.cc
+++ b/libstdc++-v3/testsuite/30_threads/shared_future/requirements/explicit_instantiation.cc
@@ -1,7 +1,6 @@
// { dg-do compile { target c++11 } }
// { dg-require-cstdint "" }
// { dg-require-gthreads "" }
-// { dg-require-atomic-builtins "" }
// Copyright (C) 2009-2016 Free Software Foundation, Inc.
//