@@ -65,7 +65,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp>
inline constexpr bool __platform_wait_uses_type
#ifdef _GLIBCXX_HAVE_LINUX_FUTEX
- = is_same_v<remove_cv_t<_Tp>, __platform_wait_t>;
+ = sizeof(_Tp) == sizeof(__platform_wait_t) &&
+ alignof(_Tp) >= alignof(__platform_wait_t);
#else
= false;
#endif
@@ -91,13 +92,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
template<typename _Tp>
void
- __platform_wait(const _Tp* __addr, __platform_wait_t __val) noexcept
+ __platform_wait(const _Tp* __addr, _Tp __val) noexcept
{
for(;;)
{
auto __e = syscall (SYS_futex, static_cast<const void*>(__addr),
static_cast<int>(__futex_wait_flags::__wait_private),
- __val, nullptr);
+ static_cast<__platform_wait_t>(__val), nullptr);
if (!__e || errno == EAGAIN)
break;
else if (errno != EINTR)
The kernel doesn't care what we store in those 32 bits, only that they are comparable. This commit adds: * pointers and long on 32-bit architectures * unsigned * untyped enums and typed enums on int & unsigned int * float We're not using FUTEX_OP anywhere today. The kernel reserves 4 bits for this field but has only used 6 values so far, so it can be extended to unsigned compares in the future, if needed. libstdc++-v3/ChangeLog: * include/bits/atomic_wait.h: Update __platform_wait_uses_type --- libstdc++-v3/include/bits/atomic_wait.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)