@@ -112,13 +112,13 @@ namespace pmr
mutex mx;
memory_resource* val;
- memory_resource* load()
+ memory_resource* load(std::memory_order)
{
lock_guard<mutex> lock(mx);
return val;
}
- memory_resource* exchange(memory_resource* r)
+ memory_resource* exchange(memory_resource* r, std::memory_order)
{
lock_guard<mutex> lock(mx);
return std::__exchange(val, r);
@@ -134,12 +134,12 @@ namespace pmr
memory_resource* val;
- memory_resource* load() const
+ memory_resource* load(std::memory_order) const
{
return val;
}
- memory_resource* exchange(memory_resource* r)
+ memory_resource* exchange(memory_resource* r, std::memory_order)
{
return std::__exchange(val, r);
}
@@ -166,12 +166,12 @@ namespace pmr
{
if (r == nullptr)
r = new_delete_resource();
- return default_res.obj.exchange(r);
+ return default_res.obj.exchange(r, std::memory_order_acq_rel);
}
memory_resource*
get_default_resource() noexcept
- { return default_res.obj.load(); }
+ { return default_res.obj.load(std::memory_order_acquire); }
// Member functions for std::pmr::monotonic_buffer_resource
Tested powerpc64le-linux, pushed to trunk. -- >8 -- Currently pmr::set_default_resource and pmr::get_default_resource both use sequentially consistent memory ordering. This is overkill. The standard only requires that a call to set_default_resource synchronizes with subsequent calls to set_default_resource and get_default_resource. Using acquire-release for the setter and acquire for the getter is sufficient to meet the requirement. Reviewed-by: Thomas Rodgers <trodgers@redhat.com> libstdc++-v3/ChangeLog: * src/c++17/memory_resource.cc (set_default_resource): Use memory_order_acq_rel. (get_default_resource): Use memory_order_acquire. --- libstdc++-v3/src/c++17/memory_resource.cc | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)