llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang-static-analyzer-1 Author: Endre Fülöp (gamesh411) <details> <summary>Changes</summary> - Enhanced descriptions for blocking and critical section functions - Added an additional code sample highlighting interleaved C and C++ style mutexes - Introduced a new section on limitations --- Full diff: https://github.com/llvm/llvm-project/pull/93812.diff 1 Files Affected: - (modified) clang/docs/analyzer/checkers.rst (+22-8) ``````````diff diff --git a/clang/docs/analyzer/checkers.rst b/clang/docs/analyzer/checkers.rst index 3a31708a1e9de..58adc0e62173a 100644 --- a/clang/docs/analyzer/checkers.rst +++ b/clang/docs/analyzer/checkers.rst @@ -3135,19 +3135,33 @@ alpha.unix alpha.unix.BlockInCriticalSection (C) """"""""""""""""""""""""""""""""""""" Check for calls to blocking functions inside a critical section. -Applies to: ``lock, unlock, sleep, getc, fgets, read, recv, pthread_mutex_lock,`` -`` pthread_mutex_unlock, mtx_lock, mtx_timedlock, mtx_trylock, mtx_unlock, lock_guard, unique_lock`` +Blocking functions detected by this checker: ``sleep, getc, fgets, read, recv``. +Critical section handling functions modelled by this checker: ``lock, unlock, pthread_mutex_lock, pthread_mutex_trylock, pthread_mutex_unlock, mtx_lock, mtx_timedlock, mtx_trylock, mtx_unlock, lock_guard, unique_lock``. .. code-block:: c - void test() { - std::mutex m; - m.lock(); - sleep(3); // warn: a blocking function sleep is called inside a critical - // section - m.unlock(); + void pthread_lock_example(pthread_mutex_t *m) { + pthread_mutex_lock(m); // note: entering critical section here + sleep(10); // warn: Call to blocking function 'sleep' inside of critical section + pthread_mutex_unlock(m); + } + +.. code-block:: cpp + + void overlapping_critical_sections(mtx_t *m1, std::mutex &m2) { + std::lock_guard lg{m2}; // note: entering critical section here + mtx_lock(m1); // note: entering critical section here + sleep(10); // warn: Call to blocking function 'sleep' inside of critical section + mtx_unlock(m1); + sleep(10); // warn: Call to blocking function 'sleep' inside of critical section + // still inside of the critical section of the std::lock_guard } +**Limitations** + +* The ``trylock`` and ``timedlock`` versions of acquiring locks are currently handled as if they always succeeded. + This can lead to false positives. + .. _alpha-unix-Chroot: alpha.unix.Chroot (C) `````````` </details> https://github.com/llvm/llvm-project/pull/93812 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
