[gcc r15-3807] libstdc++: operator new/delete are transaction_safe

[Jason Merrill]

https://gcc.gnu.org/g:2620e3727d9559ec03f9f967ecb68ed2e076a342

commit r15-3807-g2620e3727d9559ec03f9f967ecb68ed2e076a342
Author: Jason Merrill <jason@redhat.com>
Date:   Mon Sep 9 11:20:02 2024 -0400

    libstdc++: operator new/delete are transaction_safe
    
    With the changes to #pragma system_header, g++.dg/tm/pr46270.C was
    failing because <new> didn't implement the N4514 change to [new.delete] that
    says "The library versions of the global allocation and deallocation
    functions are declared transaction_safe (8.3.5 dcl.fct)."  We already have
    the _GLIBCXX_TXN_SAFE macro, just need to add it.
    
    libstdc++-v3/ChangeLog:
    
            * libsupc++/new: Add _GLIBCXX_TXN_SAFE.

Diff:
---
 libstdc++-v3/libsupc++/new | 56 +++++++++++++++++++++++++++++++---------------
 1 file changed, 38 insertions(+), 18 deletions(-)

diff --git a/libstdc++-v3/libsupc++/new b/libstdc++-v3/libsupc++/new
index b530bd1100df..e8b00505cf1e 100644
--- a/libstdc++-v3/libsupc++/new
+++ b/libstdc++-v3/libsupc++/new
@@ -132,49 +132,63 @@ namespace std
  *  Placement new and delete signatures (take a memory address argument,
  *  does nothing) may not be replaced by a user's program.
 */
-_GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
+_GLIBCXX_NODISCARD void* operator new(std::size_t)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
   __attribute__((__externally_visible__));
-_GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
+_GLIBCXX_NODISCARD void* operator new[](std::size_t)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_THROW (std::bad_alloc)
   __attribute__((__externally_visible__));
-void operator delete(void*) _GLIBCXX_USE_NOEXCEPT
+void operator delete(void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
-void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT
+void operator delete[](void*) _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
 #if __cpp_sized_deallocation
-void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
+void operator delete(void*, std::size_t)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
-void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
+void operator delete[](void*, std::size_t)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
 #endif
-_GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
+_GLIBCXX_NODISCARD void* operator new(std::size_t, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
-_GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
+_GLIBCXX_NODISCARD void* operator new[](std::size_t, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
-void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
+void operator delete(void*, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
-void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
+void operator delete[](void*, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
   __attribute__((__externally_visible__));
 #if __cpp_aligned_new
 _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
+  _GLIBCXX_TXN_SAFE
   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
 _GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
+   _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
-void operator delete(void*, std::align_val_t)
+void operator delete(void*, std::align_val_t) _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
 void operator delete(void*, std::align_val_t, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
 _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
+  _GLIBCXX_TXN_SAFE
   __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
 _GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__, __alloc_size__ (1), __malloc__));
-void operator delete[](void*, std::align_val_t)
+void operator delete[](void*, std::align_val_t) _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
 void operator delete[](void*, std::align_val_t, const std::nothrow_t&)
+  _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
 #if __cpp_sized_deallocation
-void operator delete(void*, std::size_t, std::align_val_t)
+void operator delete(void*, std::size_t, std::align_val_t) _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
-void operator delete[](void*, std::size_t, std::align_val_t)
+void operator delete[](void*, std::size_t, std::align_val_t) _GLIBCXX_TXN_SAFE
   _GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
 #endif // __cpp_sized_deallocation
 #endif // __cpp_aligned_new
@@ -187,17 +201,23 @@ void operator delete[](void*, std::size_t, std::align_val_t)
 
 // Default placement versions of operator new.
 _GLIBCXX_NODISCARD _GLIBCXX_PLACEMENT_CONSTEXPR
-void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
+void* operator new(std::size_t, void* __p)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
 { return __p; }
 _GLIBCXX_NODISCARD _GLIBCXX_PLACEMENT_CONSTEXPR
-void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
+void* operator new[](std::size_t, void* __p)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
 { return __p; }
 
 #undef _GLIBCXX_PLACEMENT_CONSTEXPR
 
 // Default placement versions of operator delete.
-inline void operator delete  (void*, void*) _GLIBCXX_USE_NOEXCEPT { }
-inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { }
+inline void operator delete  (void*, void*)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
+{ }
+inline void operator delete[](void*, void*)
+  _GLIBCXX_TXN_SAFE _GLIBCXX_USE_NOEXCEPT
+{ }
 //@}
 } // extern "C++"