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Arm Compiler armclang Reference Guide : Thread support library

Thread support library

Describes implementation-defined aspects of the Arm® C++ compiler and C++ library relating to the thread support library, as required by the ISO C++ Standard.

Presence and meaning of native_handle_type and native_handle.
The library uses the following native handles as part of the thread portability mechanism, which is described elsewhere.
__ARM_TPL_mutex_t used in std::mutex and std::recursive_mutex
__ARM_TPL_condvar_t used in std::condition_variable

__ARM_TPL_thread_id used in std::thread

__ARM_TPL_thread_t used in std::thread