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authorJonathan Wakely <jwakely@redhat.com>2020-12-17 13:16:02 +0000
committerJonathan Wakely <jwakely@redhat.com>2020-12-17 14:03:00 +0000
commit9f9dbc8e09cf48406aa24b6c78735f1a7912cc4e (patch)
tree48e7472d1f0e7e6d19e3bd69a277e44e5dda8f27
parent8dc63f13f03facc49b777195c9068432477b5dcd (diff)
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libstdc++: Fix -Wunused warning
As noted in PR 66146 comment 35, there is a new warning in the new std::call_once implementation. libstdc++-v3/ChangeLog: * src/c++11/mutex.cc (std::once_flag::_M_finish): Add maybe_unused attribute to variable used in assertion.
-rw-r--r--libstdc++-v3/src/c++11/mutex.cc3
1 files changed, 2 insertions, 1 deletions
diff --git a/libstdc++-v3/src/c++11/mutex.cc b/libstdc++-v3/src/c++11/mutex.cc
index 4d42bed..93a5eae 100644
--- a/libstdc++-v3/src/c++11/mutex.cc
+++ b/libstdc++-v3/src/c++11/mutex.cc
@@ -74,7 +74,8 @@ std::once_flag::_M_finish(bool returning) noexcept
}
else
{
- int prev = __atomic_exchange_n(&_M_once, newval, __ATOMIC_RELEASE);
+ int prev [[maybe_unused]]
+ = __atomic_exchange_n(&_M_once, newval, __ATOMIC_RELEASE);
__glibcxx_assert(prev & _Bits::_Active);
// Wake any other threads waiting for this execution to finish.
constexpr int futex_wake = 129; // FUTEX_WAKE_PRIVATE