[libc-commits] [PATCH] D79828: [libc] Add implementation of call_once from threads.h.

[Alex Brachet via Phabricator via libc-commits]

abrachet added inline comments.


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Comment at: libc/src/threads/call_once.cpp:21
+  atomic_uint *atomic_flag = reinterpret_cast<atomic_uint *>(flag);
+  unsigned int not_called = 0;
+
----------------
Should we use `ONCE_FLAG_INIT` instead of 0?


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Comment at: libc/test/src/threads/call_once_test.cpp:27
+  static once_flag flag = ONCE_FLAG_INIT;
+  call_once(&flag, call_once_func);
+
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This and the `mtx_*` functions are not prefaced with `__llvm_libc::`


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Comment at: libc/test/src/threads/call_once_test.cpp:29-31
+  mtx_lock(&thread_count_mtx);
+  ++thread_count;
+  mtx_unlock(&thread_count_mtx);
----------------
Maybe we could just make `thread_count` an atomic type so we're only testing `call_once` and not `mtx_*`?

Are there some architectures don't have support for locking instructions and must call into libc to support atomic types?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D79828/new/

https://reviews.llvm.org/D79828