libstdc++: Fix constexpr constructor for atomic<shared_ptr<T>>
libstdc++-v3/ChangeLog:
* include/bits/shared_ptr_atomic.h (_Sp_atomic::_Atomic_count):
Add constexpr.
(_Sp_atomic::_M_ptr): Add default member-initializer.
* testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc:
Check constant initialization.
* testsuite/20_util/weak_ptr/atomic_weak_ptr.cc: Likewise.
diff --git a/libstdc++-v3/include/bits/shared_ptr_atomic.h b/libstdc++-v3/include/bits/shared_ptr_atomic.h
index 35f781d..9e4df7d 100644
--- a/libstdc++-v3/include/bits/shared_ptr_atomic.h
+++ b/libstdc++-v3/include/bits/shared_ptr_atomic.h
@@ -357,7 +357,7 @@
// Ensure we can use the LSB as the lock bit.
static_assert(alignof(remove_pointer_t<pointer>) > 1);
- _Atomic_count() : _M_val(0) { }
+ constexpr _Atomic_count() noexcept = default;
explicit
_Atomic_count(__count_type&& __c) noexcept
@@ -457,7 +457,7 @@
static constexpr uintptr_t _S_lock_bit{1};
};
- typename _Tp::element_type* _M_ptr;
+ typename _Tp::element_type* _M_ptr = nullptr;
_Atomic_count _M_refcount;
static typename _Atomic_count::pointer
diff --git a/libstdc++-v3/testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc b/libstdc++-v3/testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc
index 725e7ba..1f97224 100644
--- a/libstdc++-v3/testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc
+++ b/libstdc++-v3/testsuite/20_util/shared_ptr/atomic/atomic_shared_ptr.cc
@@ -16,6 +16,9 @@
#include <testsuite_hooks.h>
+// Check constexpr constructor.
+constinit std::atomic<std::shared_ptr<int>> a;
+
void
test_is_lock_free()
{
diff --git a/libstdc++-v3/testsuite/20_util/weak_ptr/atomic_weak_ptr.cc b/libstdc++-v3/testsuite/20_util/weak_ptr/atomic_weak_ptr.cc
index e394e55..b38cea7 100644
--- a/libstdc++-v3/testsuite/20_util/weak_ptr/atomic_weak_ptr.cc
+++ b/libstdc++-v3/testsuite/20_util/weak_ptr/atomic_weak_ptr.cc
@@ -8,6 +8,9 @@
#include <thread>
#include <testsuite_hooks.h>
+// Check constexpr constructor.
+constinit std::atomic<std::weak_ptr<int>> a;
+
void
test_is_lock_free()
{
