diff mbox series

PR libstdc++/88996 Implement P0439R0 - C++20 - Make std::memory_order a scoped enumeration.

Message ID 17c5a908-dd03-5bff-2f80-a30eb33fd199@verizon.net
State New
Headers show
Series PR libstdc++/88996 Implement P0439R0 - C++20 - Make std::memory_order a scoped enumeration. | expand

Commit Message

Ed Smith-Rowland Jan. 24, 2019, 7:50 p.m. UTC 
Greetings,

This makes memory_order in <atomic> a scoped enum *only* for C++20.

This is built and tested on x86_64-linux.

OK?

2019-01-24  Edward Smith-Rowland  <3dw4rd@verizon.net>

	PR libstdc++/88996 Implement P0439R0
	Make std::memory_order a scoped enumeration.
	* include/bits/atomic_base.h: For C++20 make memory_order a scoped enum,
	add assignments for the old constants.  Adjust calls.
	* testsuite/29_atomics/headers/atomic/types_std_c++2a.cc: New test.
	* testsuite/29_atomics/headers/atomic/types_std_c++2a_neg.cc: New test.

Comments

Jonathan Wakely March 4, 2019, 8:05 p.m. UTC | #1 
On 04/02/19 14:26 +0000, Jonathan Wakely wrote:
>On 24/01/19 14:50 -0500, Ed Smith-Rowland wrote:
>>	PR libstdc++/88996 Implement P0439R0
>>	Make std::memory_order a scoped enumeration.
>>	* include/bits/atomic_base.h: For C++20 make memory_order a scoped enum,
>>	add assignments for the old constants.  Adjust calls.
>
>I think it would be more accurate to say "variables for the old
>enumerators" rather than "assignments for the old constants".
>
>As this only affects C++2a it's OK for trunk now, thanks.

Hi Ed, it looks like this wasn't committed yet. Could you please go
ahead and commit it to trunk (ideally with the changelog tweak I
suggested above).

Thanks!
Ed Smith-Rowland March 4, 2019, 8:16 p.m. UTC | #2 
On 3/4/19 3:05 PM, Jonathan Wakely wrote:
> On 04/02/19 14:26 +0000, Jonathan Wakely wrote:
>> On 24/01/19 14:50 -0500, Ed Smith-Rowland wrote:
>>>     PR libstdc++/88996 Implement P0439R0
>>>     Make std::memory_order a scoped enumeration.
>>>     * include/bits/atomic_base.h: For C++20 make memory_order a 
>>> scoped enum,
>>>     add assignments for the old constants.  Adjust calls.
>>
>> I think it would be more accurate to say "variables for the old
>> enumerators" rather than "assignments for the old constants".
>>
>> As this only affects C++2a it's OK for trunk now, thanks.
Somehow I missed this.
> Hi Ed, it looks like this wasn't committed yet. Could you please go
> ahead and commit it to trunk (ideally with the changelog tweak I
> suggested above).
>
> Thanks!
>
Done.

Thank you.

Ed


I
diff mbox series

Patch

Index: include/bits/atomic_base.h
===================================================================
--- include/bits/atomic_base.h	(revision 268246)
+++ include/bits/atomic_base.h	(working copy)
@@ -52,6 +52,24 @@ 
    */
 
   /// Enumeration for memory_order
+#if __cplusplus > 201703L
+  enum class memory_order : int
+    {
+      relaxed,
+      consume,
+      acquire,
+      release,
+      acq_rel,
+      seq_cst
+    };
+
+  inline constexpr memory_order memory_order_relaxed = memory_order::relaxed;
+  inline constexpr memory_order memory_order_consume = memory_order::consume;
+  inline constexpr memory_order memory_order_acquire = memory_order::acquire;
+  inline constexpr memory_order memory_order_release = memory_order::release;
+  inline constexpr memory_order memory_order_acq_rel = memory_order::acq_rel;
+  inline constexpr memory_order memory_order_seq_cst = memory_order::seq_cst;
+#else
   typedef enum memory_order
     {
       memory_order_relaxed,
@@ -61,6 +79,7 @@ 
       memory_order_acq_rel,
       memory_order_seq_cst
     } memory_order;
+#endif
 
   enum __memory_order_modifier
     {
@@ -73,13 +92,13 @@ 
   constexpr memory_order
   operator|(memory_order __m, __memory_order_modifier __mod)
   {
-    return memory_order(__m | int(__mod));
+    return memory_order(int(__m) | int(__mod));
   }
 
   constexpr memory_order
   operator&(memory_order __m, __memory_order_modifier __mod)
   {
-    return memory_order(__m & int(__mod));
+    return memory_order(int(__m) & int(__mod));
   }
 
   // Drop release ordering as per [atomics.types.operations.req]/21
@@ -94,16 +113,16 @@ 
   __cmpexch_failure_order(memory_order __m) noexcept
   {
     return memory_order(__cmpexch_failure_order2(__m & __memory_order_mask)
-      | (__m & __memory_order_modifier_mask));
+      | __memory_order_modifier(__m & __memory_order_modifier_mask));
   }
 
   _GLIBCXX_ALWAYS_INLINE void
   atomic_thread_fence(memory_order __m) noexcept
-  { __atomic_thread_fence(__m); }
+  { __atomic_thread_fence(int(__m)); }
 
   _GLIBCXX_ALWAYS_INLINE void
   atomic_signal_fence(memory_order __m) noexcept
-  { __atomic_signal_fence(__m); }
+  { __atomic_signal_fence(int(__m)); }
 
   /// kill_dependency
   template<typename _Tp>
@@ -173,13 +192,13 @@ 
     _GLIBCXX_ALWAYS_INLINE bool
     test_and_set(memory_order __m = memory_order_seq_cst) noexcept
     {
-      return __atomic_test_and_set (&_M_i, __m);
+      return __atomic_test_and_set (&_M_i, int(__m));
     }
 
     _GLIBCXX_ALWAYS_INLINE bool
     test_and_set(memory_order __m = memory_order_seq_cst) volatile noexcept
     {
-      return __atomic_test_and_set (&_M_i, __m);
+      return __atomic_test_and_set (&_M_i, int(__m));
     }
 
     _GLIBCXX_ALWAYS_INLINE void
@@ -190,7 +209,7 @@ 
       __glibcxx_assert(__b != memory_order_acquire);
       __glibcxx_assert(__b != memory_order_acq_rel);
 
-      __atomic_clear (&_M_i, __m);
+      __atomic_clear (&_M_i, int(__m));
     }
 
     _GLIBCXX_ALWAYS_INLINE void
@@ -201,7 +220,7 @@ 
       __glibcxx_assert(__b != memory_order_acquire);
       __glibcxx_assert(__b != memory_order_acq_rel);
 
-      __atomic_clear (&_M_i, __m);
+      __atomic_clear (&_M_i, int(__m));
     }
 
   private:
@@ -374,7 +393,7 @@ 
 	__glibcxx_assert(__b != memory_order_acq_rel);
 	__glibcxx_assert(__b != memory_order_consume);
 
-	__atomic_store_n(&_M_i, __i, __m);
+	__atomic_store_n(&_M_i, __i, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE void
@@ -386,7 +405,7 @@ 
 	__glibcxx_assert(__b != memory_order_acq_rel);
 	__glibcxx_assert(__b != memory_order_consume);
 
-	__atomic_store_n(&_M_i, __i, __m);
+	__atomic_store_n(&_M_i, __i, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
@@ -396,7 +415,7 @@ 
 	__glibcxx_assert(__b != memory_order_release);
 	__glibcxx_assert(__b != memory_order_acq_rel);
 
-	return __atomic_load_n(&_M_i, __m);
+	return __atomic_load_n(&_M_i, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
@@ -406,7 +425,7 @@ 
 	__glibcxx_assert(__b != memory_order_release);
 	__glibcxx_assert(__b != memory_order_acq_rel);
 
-	return __atomic_load_n(&_M_i, __m);
+	return __atomic_load_n(&_M_i, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
@@ -413,7 +432,7 @@ 
       exchange(__int_type __i,
 	       memory_order __m = memory_order_seq_cst) noexcept
       {
-	return __atomic_exchange_n(&_M_i, __i, __m);
+	return __atomic_exchange_n(&_M_i, __i, int(__m));
       }
 
 
@@ -421,7 +440,7 @@ 
       exchange(__int_type __i,
 	       memory_order __m = memory_order_seq_cst) volatile noexcept
       {
-	return __atomic_exchange_n(&_M_i, __i, __m);
+	return __atomic_exchange_n(&_M_i, __i, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -434,7 +453,8 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -448,7 +468,8 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 1,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -477,7 +498,8 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -492,7 +514,8 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_i, &__i1, __i2, 0,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -514,52 +537,52 @@ 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_add(__int_type __i,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_add(&_M_i, __i, __m); }
+      { return __atomic_fetch_add(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_add(__int_type __i,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_add(&_M_i, __i, __m); }
+      { return __atomic_fetch_add(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_sub(__int_type __i,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_sub(&_M_i, __i, __m); }
+      { return __atomic_fetch_sub(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_sub(__int_type __i,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_sub(&_M_i, __i, __m); }
+      { return __atomic_fetch_sub(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_and(__int_type __i,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_and(&_M_i, __i, __m); }
+      { return __atomic_fetch_and(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_and(__int_type __i,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_and(&_M_i, __i, __m); }
+      { return __atomic_fetch_and(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_or(__int_type __i,
 	       memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_or(&_M_i, __i, __m); }
+      { return __atomic_fetch_or(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_or(__int_type __i,
 	       memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_or(&_M_i, __i, __m); }
+      { return __atomic_fetch_or(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_xor(__int_type __i,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_xor(&_M_i, __i, __m); }
+      { return __atomic_fetch_xor(&_M_i, __i, int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __int_type
       fetch_xor(__int_type __i,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_xor(&_M_i, __i, __m); }
+      { return __atomic_fetch_xor(&_M_i, __i, int(__m)); }
     };
 
 
@@ -691,7 +714,7 @@ 
 	__glibcxx_assert(__b != memory_order_acq_rel);
 	__glibcxx_assert(__b != memory_order_consume);
 
-	__atomic_store_n(&_M_p, __p, __m);
+	__atomic_store_n(&_M_p, __p, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE void
@@ -703,7 +726,7 @@ 
 	__glibcxx_assert(__b != memory_order_acq_rel);
 	__glibcxx_assert(__b != memory_order_consume);
 
-	__atomic_store_n(&_M_p, __p, __m);
+	__atomic_store_n(&_M_p, __p, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
@@ -713,7 +736,7 @@ 
 	__glibcxx_assert(__b != memory_order_release);
 	__glibcxx_assert(__b != memory_order_acq_rel);
 
-	return __atomic_load_n(&_M_p, __m);
+	return __atomic_load_n(&_M_p, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
@@ -723,7 +746,7 @@ 
 	__glibcxx_assert(__b != memory_order_release);
 	__glibcxx_assert(__b != memory_order_acq_rel);
 
-	return __atomic_load_n(&_M_p, __m);
+	return __atomic_load_n(&_M_p, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
@@ -730,7 +753,7 @@ 
       exchange(__pointer_type __p,
 	       memory_order __m = memory_order_seq_cst) noexcept
       {
-	return __atomic_exchange_n(&_M_p, __p, __m);
+	return __atomic_exchange_n(&_M_p, __p, int(__m));
       }
 
 
@@ -738,7 +761,7 @@ 
       exchange(__pointer_type __p,
 	       memory_order __m = memory_order_seq_cst) volatile noexcept
       {
-	return __atomic_exchange_n(&_M_p, __p, __m);
+	return __atomic_exchange_n(&_M_p, __p, int(__m));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -752,7 +775,8 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE bool
@@ -767,28 +791,29 @@ 
 	__glibcxx_assert(__b2 != memory_order_acq_rel);
 	__glibcxx_assert(__b2 <= __b1);
 
-	return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0, __m1, __m2);
+	return __atomic_compare_exchange_n(&_M_p, &__p1, __p2, 0,
+					   int(__m1), int(__m2));
       }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
       fetch_add(ptrdiff_t __d,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
+      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
       fetch_add(ptrdiff_t __d,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), __m); }
+      { return __atomic_fetch_add(&_M_p, _M_type_size(__d), int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
       fetch_sub(ptrdiff_t __d,
 		memory_order __m = memory_order_seq_cst) noexcept
-      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
+      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), int(__m)); }
 
       _GLIBCXX_ALWAYS_INLINE __pointer_type
       fetch_sub(ptrdiff_t __d,
 		memory_order __m = memory_order_seq_cst) volatile noexcept
-      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), __m); }
+      { return __atomic_fetch_sub(&_M_p, _M_type_size(__d), int(__m)); }
     };
 
   // @} group atomics
Index: testsuite/29_atomics/headers/atomic/types_std_c++2a.cc
===================================================================
--- testsuite/29_atomics/headers/atomic/types_std_c++2a.cc	(nonexistent)
+++ testsuite/29_atomics/headers/atomic/types_std_c++2a.cc	(working copy)
@@ -0,0 +1,32 @@ 
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library 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.
+//
+// This library 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.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <atomic>
+
+void test01()
+{
+  using std::memory_order;
+  constexpr auto relaxed = memory_order::relaxed;
+  constexpr auto consume = memory_order::consume;
+  constexpr auto acquire = memory_order::acquire;
+  constexpr auto release = memory_order::release;
+  constexpr auto acq_rel = memory_order::acq_rel;
+  constexpr auto seq_cst = memory_order::seq_cst;
+}
Index: testsuite/29_atomics/headers/atomic/types_std_c++2a_neg.cc
===================================================================
--- testsuite/29_atomics/headers/atomic/types_std_c++2a_neg.cc	(nonexistent)
+++ testsuite/29_atomics/headers/atomic/types_std_c++2a_neg.cc	(working copy)
@@ -0,0 +1,33 @@ 
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library 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.
+//
+// This library 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.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <atomic>
+
+void test01()
+{
+  // Not global scoped, only namespace std.
+  using memory_order; // { dg-error "expected nested-name-specifier" }
+  constexpr auto relaxed = memory_order::relaxed; // { dg-error "has not been declared" }
+  constexpr auto consume = memory_order::consume; // { dg-error "has not been declared" }
+  constexpr auto acquire = memory_order::acquire; // { dg-error "has not been declared" }
+  constexpr auto release = memory_order::release; // { dg-error "has not been declared" }
+  constexpr auto acq_rel = memory_order::acq_rel; // { dg-error "has not been declared" }
+  constexpr auto seq_cst = memory_order::seq_cst; // { dg-error "has not been declared" }
+}