diff --git a/googletest/src/gtest-port.cc b/googletest/src/gtest-port.cc index d80bd80c..edd115df 100644 --- a/googletest/src/gtest-port.cc +++ b/googletest/src/gtest-port.cc @@ -279,6 +279,43 @@ void Mutex::AssertHeld() { << "The current thread is not holding the mutex @" << this; } +namespace { + +// Use the RAII idiom to flag mem allocs that are intentionally never +// deallocated. The motivation is to silence the false positive mem leaks +// that are reported by the debug version of MS's CRT which can only detect +// if an alloc is missing a matching deallocation. +// Example: +// MemoryIsNotDeallocated memory_is_not_deallocated; +// critical_section_ = new CRITICAL_SECTION; +// +class MemoryIsNotDeallocated +{ +public: + MemoryIsNotDeallocated() : old_crtdbg_flag_(0) { +#ifdef _MSC_VER + old_crtdbg_flag_ = _CrtSetDbgFlag(_CRTDBG_REPORT_FLAG); + // Set heap allocation block type to _IGNORE_BLOCK so that MS debug CRT + // doesn't report mem leak if there's no matching deallocation. + _CrtSetDbgFlag(old_crtdbg_flag_ & ~_CRTDBG_ALLOC_MEM_DF); +#endif // _MSC_VER + } + + ~MemoryIsNotDeallocated() { +#ifdef _MSC_VER + // Restore the original _CRTDBG_ALLOC_MEM_DF flag + _CrtSetDbgFlag(old_crtdbg_flag_); +#endif // _MSC_VER + } + +private: + int old_crtdbg_flag_; + + GTEST_DISALLOW_COPY_AND_ASSIGN_(MemoryIsNotDeallocated); +}; + +} // namespace + // Initializes owner_thread_id_ and critical_section_ in static mutexes. void Mutex::ThreadSafeLazyInit() { // Dynamic mutexes are initialized in the constructor. @@ -289,7 +326,11 @@ void Mutex::ThreadSafeLazyInit() { // If critical_section_init_phase_ was 0 before the exchange, we // are the first to test it and need to perform the initialization. owner_thread_id_ = 0; - critical_section_ = new CRITICAL_SECTION; + { + // Use RAII to flag that following mem alloc is never deallocated. + MemoryIsNotDeallocated memory_is_not_deallocated; + critical_section_ = new CRITICAL_SECTION; + } ::InitializeCriticalSection(critical_section_); // Updates the critical_section_init_phase_ to 2 to signal // initialization complete. @@ -528,10 +569,17 @@ class ThreadLocalRegistryImpl { return 0; } + // Return a newly constructed ThreadIdToThreadLocals that's intentionally never deleted + static ThreadIdToThreadLocals* NewThreadIdToThreadLocals() { + // Use RAII to flag that following mem alloc is never deallocated. + MemoryIsNotDeallocated memory_is_not_deallocated; + return new ThreadIdToThreadLocals; + } + // Returns map of thread local instances. static ThreadIdToThreadLocals* GetThreadLocalsMapLocked() { mutex_.AssertHeld(); - static ThreadIdToThreadLocals* map = new ThreadIdToThreadLocals; + static ThreadIdToThreadLocals* map = NewThreadIdToThreadLocals(); return map; }