On 04/12/19 17:56 -0500, JeanHeyd Meneide wrote:
Dear Jonathan,
Done! re-patched, below.
Thanks!
Some comments below.
Best,
JeanHeyd
2019-12-03 JeanHeyd "ThePhD" Meneide <phdoftheho...@gmail.com>
* include/bits/c++config: Add new _GLIBCXX20_DEPRECATED macro.
* include/std/type_traits: Deprecate is_pod with message.
* testuite/20_util/is_pod/deprecated-2a.cc (new): test deprecation
The parenthesis after the filename should tell you the entity that was
changed, so something like:
* include/bits/c++config (_GLIBCXX20_DEPRECATED): Add new macro.
* include/std/type_traits (is_pod, is_pod_v): Deprecate for C++20.
* testuite/20_util/is_pod/deprecated-2a.cc: New test.
This tells you that _GLIBCXX20_DEPRECATED is the new macro, and that
is_pod and is_pod_v were deprecated.
diff --git a/libstdc++-v3/include/bits/c++config
b/libstdc++-v3/include/bits/c++config
index 7ccfc5f199d..9e85fc2c9e8 100644
--- a/libstdc++-v3/include/bits/c++config
+++ b/libstdc++-v3/include/bits/c++config
@@ -78,6 +78,7 @@
// _GLIBCXX_USE_DEPRECATED
// _GLIBCXX_DEPRECATED
// _GLIBCXX17_DEPRECATED
+// _GLIBCXX20_DEPRECATED( STRINGS... )
#ifndef _GLIBCXX_USE_DEPRECATED
# define _GLIBCXX_USE_DEPRECATED 1
#endif
@@ -94,6 +95,12 @@
# define _GLIBCXX17_DEPRECATED
#endif
+#if defined(__DEPRECATED) && (__cplusplus > 201703L)
+# define _GLIBCXX20_DEPRECATED(MSG) [[deprecated(MSG)]]
+#else
+# define _GLIBCXX20_DEPRECATED(MSG)
+#endif
+
// Macros for ABI tag attributes.
#ifndef _GLIBCXX_ABI_TAG_CXX11
# define _GLIBCXX_ABI_TAG_CXX11 __attribute ((__abi_tag__ ("cxx11")))
diff --git a/libstdc++-v3/include/std/type_traits
b/libstdc++-v3/include/std/type_traits
index 8e787a994c3..5980b21c763 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -685,10 +685,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
"template argument must be a complete class or an unbounded array");
};
- /// is_pod
+ /// is_pod (deprecated C++2a)
// Could use is_standard_layout && is_trivial instead of the builtin.
template<typename _Tp>
- struct is_pod
+ struct
+ _GLIBCXX20_DEPRECATED("is_pod<T> is deprecated in C++20: use (is_standard_layout_v<T>
&& is_trivial_v<T>) instead")
+ is_pod
: public integral_constant<bool, __is_pod(_Tp)>
{
static_assert(std::__is_complete_or_unbounded(__type_identity<_Tp>{}),
@@ -3073,6 +3075,7 @@ template <typename _Tp>
template <typename _Tp>
inline constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
template <typename _Tp>
+ _GLIBCXX20_DEPRECATED("is_pod_v<T> is deprecated in C++20: use (is_standard_layout_v<T>
&& is_trivial_v<T>) instead")
This message ends up repeating the "is deprecated":
pod.cc:6:21: warning: 'std::is_pod_v<A>' is deprecated: is_pod_v<T> is deprecated in C++20: use
(is_standard_layout_v<T> && is_trivial_v<T>) instead [-Wdeprecated-declarations]
I think we can just shorten it to the "use ... instead". Also, given
that the compiler prints the template argument list "<A>" it's a bit
confusing to also put argument lists (with different types) in the
message. I think this is better:
pod.cc:6:21: warning: 'std::is_pod_v<A>' is deprecated: use is_standard_layout_v
&& is_trivial_v instead [-Wdeprecated-declarations]
inline constexpr bool is_pod_v = is_pod<_Tp>::value;
template <typename _Tp>
inline constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
diff --git a/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc
b/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc
new file mode 100644
index 00000000000..1035a729434
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc
@@ -0,0 +1,25 @@
+// 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/>.
+
+// { dg-do compile { target c++2a } }
This test doesn't actually run:
UNSUPPORTED: 20_util/is_pod/deprecated-2a.cc
It needs { dg-options "-std=gnu++2a" }
+
+// { dg-prune-output "declared here" }
+
+#include <type_traits>
+
+static_assert(std::is_pod<int>::value); // { dg-warning "is deprecated" }
+static_assert(std::is_pod_v<int>); // { dg-warning "is deprecated" }
I'll commit the attached patch after more testing.
N.B. it looks like the implementation of [[deprecated(msg)]] isn't
working quite right, because for is_pod I don't get the message:
pod.cc:6:21: warning: 'template<class _Tp> struct std::is_pod' is deprecated
[-Wdeprecated-declarations]
6 | static_assert( std::is_pod<A>::value );
| ^~~~~~
In file included from pod.cc:1:
/home/jwakely/gcc/10/include/c++/10.0.0/type_traits:693:5: note: declared here
693 | is_pod
| ^~~~~~
It works correctly for std::is_pod_v.
commit 2afe60862e34c76f096ca442bdf245f4c02e1612
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Thu Jan 9 17:34:11 2020 +0000
libstdc++: Implementing P0767 - deprecate POD
This adds the deprecated attribute to std::is_pod and std::is_pod_v for
C++20.
2019-12-05 JeanHeyd "ThePhD" Meneide <phdoftheho...@gmail.com>
* include/bits/c++config (_GLIBCXX20_DEPRECATED): Add new macro.
* include/std/type_traits (is_pod, is_pod_v): Deprecate for C++20.
* testuite/20_util/is_pod/deprecated-2a.cc: New test.
diff --git a/libstdc++-v3/include/bits/c++config b/libstdc++-v3/include/bits/c++config
index f983743b052..875a5e76890 100644
--- a/libstdc++-v3/include/bits/c++config
+++ b/libstdc++-v3/include/bits/c++config
@@ -78,6 +78,7 @@
// _GLIBCXX_USE_DEPRECATED
// _GLIBCXX_DEPRECATED
// _GLIBCXX17_DEPRECATED
+// _GLIBCXX20_DEPRECATED( string-literal )
#ifndef _GLIBCXX_USE_DEPRECATED
# define _GLIBCXX_USE_DEPRECATED 1
#endif
@@ -94,6 +95,12 @@
# define _GLIBCXX17_DEPRECATED
#endif
+#if defined(__DEPRECATED) && (__cplusplus > 201703L)
+# define _GLIBCXX20_DEPRECATED(MSG) [[deprecated(MSG)]]
+#else
+# define _GLIBCXX20_DEPRECATED(MSG)
+#endif
+
// Macros for ABI tag attributes.
#ifndef _GLIBCXX_ABI_TAG_CXX11
# define _GLIBCXX_ABI_TAG_CXX11 __attribute ((__abi_tag__ ("cxx11")))
diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits
index 061835b8f2d..c69867c2ae0 100644
--- a/libstdc++-v3/include/std/type_traits
+++ b/libstdc++-v3/include/std/type_traits
@@ -685,10 +685,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
"template argument must be a complete class or an unbounded array");
};
- /// is_pod
+ /// is_pod (deprecated in C++20)
// Could use is_standard_layout && is_trivial instead of the builtin.
template<typename _Tp>
- struct is_pod
+ struct
+ _GLIBCXX20_DEPRECATED("use is_standard_layout && is_trivial instead")
+ is_pod
: public integral_constant<bool, __is_pod(_Tp)>
{
static_assert(std::__is_complete_or_unbounded(__type_identity<_Tp>{}),
@@ -3078,6 +3080,7 @@ template <typename _Tp>
template <typename _Tp>
inline constexpr bool is_standard_layout_v = is_standard_layout<_Tp>::value;
template <typename _Tp>
+ _GLIBCXX20_DEPRECATED("use is_standard_layout_v && is_trivial_v instead")
inline constexpr bool is_pod_v = is_pod<_Tp>::value;
template <typename _Tp>
inline constexpr bool is_literal_type_v = is_literal_type<_Tp>::value;
diff --git a/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc b/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc
new file mode 100644
index 00000000000..848baf7bcfe
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/is_pod/deprecated-2a.cc
@@ -0,0 +1,26 @@
+// Copyright (C) 2020 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/>.
+
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+
+#include <type_traits>
+
+static_assert(std::is_pod<int>::value); // { dg-warning "is deprecated" }
+static_assert(std::is_pod_v<int>); // { dg-warning "is deprecated" }
+
+// { dg-prune-output "declared here" }
