[libcxx-commits] [PATCH] D154354: [libc++] Fix thread annotations on shared_mutex and shared_timed_mutex

[Nikolas Klauser via Phabricator via libcxx-commits]

philnik requested changes to this revision.
philnik added a comment.
This revision now requires changes to proceed.

In D154354#4469777 <https://reviews.llvm.org/D154354#4469777>, @aaronpuchert wrote:

> Thanks for picking this up!
>
> In D154354#4468666 <https://reviews.llvm.org/D154354#4468666>, @philnik wrote:
>
>> Could we add some sort of tests for this?
>
> There are several existing tests, see libcxx/test/libcxx/thread/thread.mutex/thread_safety_* <https://github.com/llvm/llvm-project/tree/main/libcxx/test/libcxx/thread/thread.mutex>. What should work:
>
>   std::shared_mutex m;
>   int data __attribute__((guarded_by(m)));
>   void read(int);
>   
>   ++foo; // warning, but probably no need to test this: libc++ has
>          // nothing to do with it, it's due to the attribute above.
>   m.lock();
>   ++foo; // ok.
>   m.unlock();
>   
>   if (m.try_lock())
>     ++foo; // ok.
>   m.unlock();
>   
>   m.lock_shared();
>   read(foo); // ok.
>   ++foo; // warning.
>   m.unlock_shared();

Then I definitely want some tests for this.



================
Comment at: libcxx/include/shared_mutex:199
     // Exclusive ownership
-    _LIBCPP_INLINE_VISIBILITY void lock()     { return __base_.lock(); }
-    _LIBCPP_INLINE_VISIBILITY bool try_lock() { return __base_.try_lock(); }
-    _LIBCPP_INLINE_VISIBILITY void unlock()   { return __base_.unlock(); }
+    _LIBCPP_INLINE_VISIBILITY void lock() _LIBCPP_THREAD_SAFETY_ANNOTATION(acquire_capability()) {
+      return __base_.lock();
----------------
As a fly-by we might as well _Uglify the attributes.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D154354/new/

https://reviews.llvm.org/D154354