diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl.h b/compiler-rt/lib/tsan/rtl/tsan_rtl.h
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl.h
@@ -698,7 +698,8 @@
   kAccessWrite = 0,
   kAccessRead = 1 << 0,
   kAccessAtomic = 1 << 1,
-  kAccessVptr = 1 << 2,
+  kAccessVptr = 1 << 2,  // read or write of an object virtual table pointer
+  kAccessFree = 1 << 3,  // synthetic memory access during memory freeing
 };
 
 void MemoryAccess(ThreadState *thr, uptr pc, uptr addr,
@@ -741,9 +742,13 @@
   bool is_atomic = typ & kAccessAtomic;
   if (typ & kAccessVptr)
     thr->is_vptr_access = true;
+  if (typ & kAccessFree)
+    thr->is_freeing = true;
   MemoryAccess(thr, pc, addr, size_log, is_write, is_atomic);
   if (typ & kAccessVptr)
     thr->is_vptr_access = false;
+  if (typ & kAccessFree)
+    thr->is_freeing = false;
 }
 
 void MemoryResetRange(ThreadState *thr, uptr pc, uptr addr, uptr size);
diff --git a/compiler-rt/lib/tsan/rtl/tsan_rtl_mutex.cpp b/compiler-rt/lib/tsan/rtl/tsan_rtl_mutex.cpp
--- a/compiler-rt/lib/tsan/rtl/tsan_rtl_mutex.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_rtl_mutex.cpp
@@ -132,12 +132,8 @@
   // Imitate a memory write to catch unlock-destroy races.
   // Do this outside of sync mutex, because it can report a race which locks
   // sync mutexes.
-  if (IsAppMem(addr)) {
-    CHECK(!thr->is_freeing);
-    thr->is_freeing = true;
-    MemoryAccess(thr, pc, addr, 1, kAccessWrite);
-    thr->is_freeing = false;
-  }
+  if (IsAppMem(addr))
+    MemoryAccess(thr, pc, addr, 1, kAccessWrite | kAccessFree);
   // s will be destroyed and freed in MetaMap::FreeBlock.
 }