Index: lib/tsan/rtl/tsan_interceptors.cc
===================================================================
--- lib/tsan/rtl/tsan_interceptors.cc
+++ lib/tsan/rtl/tsan_interceptors.cc
@@ -992,8 +992,8 @@
 INTERCEPTOR(int, pthread_cond_wait, void *c, void *m) {
   void *cond = init_cond(c);
   SCOPED_TSAN_INTERCEPTOR(pthread_cond_wait, cond, m);
-  MutexUnlock(thr, pc, (uptr)m);
   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
+  MutexUnlock(thr, pc, (uptr)m);
   CondMutexUnlockCtx arg = {&si, thr, pc, m};
   int res = 0;
   // This ensures that we handle mutex lock even in case of pthread_cancel.
@@ -1014,8 +1014,8 @@
 INTERCEPTOR(int, pthread_cond_timedwait, void *c, void *m, void *abstime) {
   void *cond = init_cond(c);
   SCOPED_TSAN_INTERCEPTOR(pthread_cond_timedwait, cond, m, abstime);
-  MutexUnlock(thr, pc, (uptr)m);
   MemoryAccessRange(thr, pc, (uptr)c, sizeof(uptr), false);
+  MutexUnlock(thr, pc, (uptr)m);
   CondMutexUnlockCtx arg = {&si, thr, pc, m};
   int res = 0;
   // This ensures that we handle mutex lock even in case of pthread_cancel.
Index: test/tsan/cond_destruction.cc
===================================================================
--- test/tsan/cond_destruction.cc
+++ test/tsan/cond_destruction.cc
@@ -0,0 +1,53 @@
+// RUN: %clangxx_tsan -O1 %s -o %t
+// RUN: %run %t 2>&1 | FileCheck %s
+// RUN: %run %t arg 2>&1 | FileCheck %s
+// RUN: %run %t arg arg 2>&1 | FileCheck %s
+#include "test.h"
+
+// Test for destruction of pthread_cond_t.
+// POSIX states that it is safe  to destroy a condition variable upon which no
+// threads are currently blocked. That is, it is not necessary to wait untill
+// other threads return from pthread_cond_wait, they just need to be unblocked.
+
+pthread_mutex_t m;
+pthread_cond_t c;
+bool done1, done2;
+
+void *thr(void *p) {
+  pthread_mutex_lock(&m);
+  done1 = true;
+  pthread_cond_signal(&c);
+  while (!done2)
+    pthread_cond_wait(&c, &m);
+  pthread_mutex_unlock(&m);
+  return 0;
+}
+
+int main(int argc, char **argv) {
+  pthread_t th;
+  pthread_mutex_init(&m, 0);
+  pthread_cond_init(&c, 0);
+  pthread_create(&th, 0, thr, 0);
+  pthread_mutex_lock(&m);
+  while (!done1)
+    pthread_cond_wait(&c, &m);
+  done2 = true;
+  // Any of these sequences is legal.
+  if (argc == 1) {
+    pthread_cond_signal(&c);
+    pthread_mutex_unlock(&m);
+    pthread_cond_destroy(&c);
+  } else if (argc == 2) {
+    pthread_mutex_unlock(&m);
+    pthread_cond_signal(&c);
+    pthread_cond_destroy(&c);
+  } else {
+    pthread_cond_signal(&c);
+    pthread_cond_destroy(&c);
+    pthread_mutex_unlock(&m);
+  }
+  pthread_join(th, 0);
+  fprintf(stderr, "DONE\n");
+}
+
+// CHECK-NOT: ThreadSanitizer: data race