diff mbox series

Deprecate std::get_temporary_buffer

Message ID 20180814203429.GC13845@redhat.com
State New
Headers show
Series Deprecate std::get_temporary_buffer | expand

Commit Message

Jonathan Wakely Aug. 14, 2018, 8:34 p.m. UTC 
This was deprecated in C++17, and has been removed from the current
draft. This adds the dprecated attribute for C++17 and later.

We can't actually remove it for C++2a because we use it (indirectly)
in stl_algo.h. We could rename it to __get_temporary_buffer for our
internal uses, and then add back get_temporary_buffer as a simple
forwarding function guarded by:

#if __cplusplus <= 201703L || _GLIBCXX_USE_DEPRECATED

This patch doesn't do that though.

Does anybody object to adding the deprecated attribute here?

Does anybody want to argue in favour of completely removing it for
C++2a?

Comments

Ville Voutilainen Aug. 14, 2018, 8:58 p.m. UTC | #1 
On 14 August 2018 at 23:34, Jonathan Wakely <jwakely@redhat.com> wrote:
> This was deprecated in C++17, and has been removed from the current
> draft. This adds the dprecated attribute for C++17 and later.
>
> We can't actually remove it for C++2a because we use it (indirectly)
> in stl_algo.h. We could rename it to __get_temporary_buffer for our
> internal uses, and then add back get_temporary_buffer as a simple
> forwarding function guarded by:
>
> #if __cplusplus <= 201703L || _GLIBCXX_USE_DEPRECATED
>
> This patch doesn't do that though.
>
> Does anybody object to adding the deprecated attribute here?

Not me.

> Does anybody want to argue in favour of completely removing it for
> C++2a?

Not me.
diff mbox series

Patch

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 182c0ed2ff3..ed2f92d0089 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,9 @@ 
 2018-08-14  Jonathan Wakely  <jwakely@redhat.com>
 
+	* include/bits/stl_tempbuf.h (get_temporary_buffer)
+	(return_temporary_buffer): Add deprecated attribute for C++17.
+	(_Temporary_buffer): Disable -Wdeprecated-declarations warnings.
+
 	PR libstdc++/86954
 	* include/bits/stl_tempbuf.h (return_temporary_buffer): Use
 	non-placement delete.
diff --git a/libstdc++-v3/include/bits/stl_tempbuf.h b/libstdc++-v3/include/bits/stl_tempbuf.h
index 0abd3c12de7..2ccaf3e3bd0 100644
--- a/libstdc++-v3/include/bits/stl_tempbuf.h
+++ b/libstdc++-v3/include/bits/stl_tempbuf.h
@@ -81,6 +81,9 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
    * Provides the nothrow exception guarantee.
    */
   template<typename _Tp>
+#if __cplusplus >= 201703L
+    _GLIBCXX_DEPRECATED
+#endif
     pair<_Tp*, ptrdiff_t>
     get_temporary_buffer(ptrdiff_t __len) _GLIBCXX_NOEXCEPT
     {
@@ -108,11 +111,13 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  Frees the memory pointed to by __p.
    */
   template<typename _Tp>
+#if __cplusplus >= 201703L
+    _GLIBCXX_DEPRECATED
+#endif
     inline void
     return_temporary_buffer(_Tp* __p)
     { ::operator delete(__p); }
 
-
   /**
    *  This class is used in two places: stl_algo.h and ext/memory,
    *  where it is wrapped as the temporary_buffer class.  See
@@ -162,11 +167,14 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
        */
       _Temporary_buffer(_ForwardIterator __seed, size_type __original_len);
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
       ~_Temporary_buffer()
       {
 	std::_Destroy(_M_buffer, _M_buffer + _M_len);
 	std::return_temporary_buffer(_M_buffer);
       }
+#pragma GCC diagnostic pop
 
     private:
       // Disable copy constructor and assignment operator.
@@ -239,6 +247,8 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  __ucr(__first, __last, __seed);
     }
 
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
   template<typename _ForwardIterator, typename _Tp>
     _Temporary_buffer<_ForwardIterator, _Tp>::
     _Temporary_buffer(_ForwardIterator __seed, size_type __original_len)
@@ -262,6 +272,7 @@  _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  __throw_exception_again;
 	}
     }
+#pragma GCC diagnostic pop
 
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace