[gcc r16-6553] libstdc++: Fix memory leak in std::barrier destructor [PR123378]

[Jonathan Wakely]

https://gcc.gnu.org/g:5b20eefe0c39c352f40bc6ff6fd995bfa0e49636

commit r16-6553-g5b20eefe0c39c352f40bc6ff6fd995bfa0e49636
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Mon Jan 5 17:29:40 2026 +0000

    libstdc++: Fix memory leak in std::barrier destructor [PR123378]
    
    When I replaced the std::unique_ptr member in r16-997-gef632273a90657 I
    should have added an explicit delete[] operation to replace the effects
    of the unique_ptr destructor.
    
    libstdc++-v3/ChangeLog:
    
            PR libstdc++/123378
            * include/std/barrier (~__tree_barrier_base): Define.
    
    Reviewed-by: Tomasz Kamiński <tkaminsk@redhat.com>

Diff:
---
 libstdc++-v3/include/std/barrier | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/libstdc++-v3/include/std/barrier b/libstdc++-v3/include/std/barrier
index 060285d6bf85..0986ff9dada6 100644
--- a/libstdc++-v3/include/std/barrier
+++ b/libstdc++-v3/include/std/barrier
@@ -114,6 +114,12 @@ It looks different from literature pseudocode for two main reasons:
 	_M_state.store(_M_alloc_state().release(), memory_order_release);
     }
 
+    ~__tree_barrier_base()
+    { delete[] _M_state.load(memory_order_relaxed); }
+
+    __tree_barrier_base(const __tree_barrier_base&&) = delete;
+    __tree_barrier_base& operator=(const __tree_barrier_base&&) = delete;
+
     unique_ptr<__state_t[]>
     _M_alloc_state()
     {