[gcc r15-284] libstdc++: Fix for -std=c++23 -ffreestanding [PR114866]

[Jonathan Wakely via Libstdc++-cvs]

https://gcc.gnu.org/g:9927059bb88e966e0a45f09e4fd1193f93df708f

commit r15-284-g9927059bb88e966e0a45f09e4fd1193f93df708f
Author: Jonathan Wakely <jwak...@redhat.com>
Date:   Thu May 2 12:14:52 2024 +0100

    libstdc++: Fix <memory> for -std=c++23 -ffreestanding [PR114866]
    
    std::shared_ptr isn't declared for freestanding, so guard uses of it
    with #if _GLIBCXX_HOSTED in <bits/out_ptr.h>.
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/114866
            * include/bits/out_ptr.h [!_GLIBCXX_HOSTED]: Don't refer to
            shared_ptr, __shared_ptr or __is_shred_ptr.
            * testsuite/20_util/headers/memory/114866.cc: New test.

Diff:
---
 libstdc++-v3/include/bits/out_ptr.h                     | 10 ++++++++++
 libstdc++-v3/testsuite/20_util/headers/memory/114866.cc |  4 ++++
 2 files changed, 14 insertions(+)

diff --git a/libstdc++-v3/include/bits/out_ptr.h 
b/libstdc++-v3/include/bits/out_ptr.h
index aeeb6640441..d74c9f52d3b 100644
--- a/libstdc++-v3/include/bits/out_ptr.h
+++ b/libstdc++-v3/include/bits/out_ptr.h
@@ -54,9 +54,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Smart, typename _Pointer, typename... _Args>
     class out_ptr_t
     {
+#if _GLIBCXX_HOSTED
       static_assert(!__is_shared_ptr<_Smart> || sizeof...(_Args) != 0,
                    "a deleter must be used when adapting std::shared_ptr "
                    "with std::out_ptr");
+#endif
 
     public:
       explicit
@@ -216,6 +218,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
          [[no_unique_address]] _Del2 _M_del;
        };
 
+#if _GLIBCXX_HOSTED
       // Partial specialization for std::shared_ptr.
       // This specialization gives direct access to the private member
       // of the shared_ptr, avoiding the overhead of storing a separate
@@ -274,6 +277,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        {
          using _Impl<_Smart, _Pointer, _Del, allocator<void>>::_Impl;
        };
+#endif
 
       using _Impl_t = _Impl<_Smart, _Pointer, _Args...>;
 
@@ -293,8 +297,10 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   template<typename _Smart, typename _Pointer, typename... _Args>
     class inout_ptr_t
     {
+#if _GLIBCXX_HOSTED
       static_assert(!__is_shared_ptr<_Smart>,
                    "std::inout_ptr can not be used to wrap std::shared_ptr");
+#endif
 
     public:
       explicit
@@ -320,11 +326,15 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       }
 
     private:
+#if _GLIBCXX_HOSTED
       // Avoid an invalid instantiation of out_ptr_t<shared_ptr<T>, ...>
       using _Out_ptr_t
        = __conditional_t<__is_shared_ptr<_Smart>,
                          out_ptr_t<void*, void*>,
                          out_ptr_t<_Smart, _Pointer, _Args...>>;
+#else
+      using _Out_ptr_t = out_ptr_t<_Smart, _Pointer, _Args...>;
+#endif
       using _Impl_t = typename _Out_ptr_t::_Impl_t;
       _Impl_t _M_impl;
     };
diff --git a/libstdc++-v3/testsuite/20_util/headers/memory/114866.cc 
b/libstdc++-v3/testsuite/20_util/headers/memory/114866.cc
new file mode 100644
index 00000000000..7cf6be0539d
--- /dev/null
+++ b/libstdc++-v3/testsuite/20_util/headers/memory/114866.cc
@@ -0,0 +1,4 @@
+// { dg-options "-ffreestanding" }
+// { dg-do compile }
+// PR libstdc++/114866 <memory> & out_ptr in freestanding
+#include <memory>