diff --git a/compiler-rt/lib/asan/asan_globals.cpp b/compiler-rt/lib/asan/asan_globals.cpp
--- a/compiler-rt/lib/asan/asan_globals.cpp
+++ b/compiler-rt/lib/asan/asan_globals.cpp
@@ -35,7 +35,7 @@
   ListOfGlobals *next;
 };
 
-static BlockingMutex mu_for_globals(LINKER_INITIALIZED);
+static Mutex mu_for_globals;
 static LowLevelAllocator allocator_for_globals;
 static ListOfGlobals *list_of_all_globals;
 
@@ -108,7 +108,7 @@
 int GetGlobalsForAddress(uptr addr, Global *globals, u32 *reg_sites,
                          int max_globals) {
   if (!flags()->report_globals) return 0;
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   int res = 0;
   for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
     const Global &g = *l->g;
@@ -257,7 +257,7 @@
 }
 
 void StopInitOrderChecking() {
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   if (!flags()->check_initialization_order || !dynamic_init_globals)
     return;
   flags()->check_initialization_order = false;
@@ -359,7 +359,7 @@
   if (!flags()->report_globals) return;
   GET_STACK_TRACE_MALLOC;
   u32 stack_id = StackDepotPut(stack);
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   if (!global_registration_site_vector) {
     global_registration_site_vector =
         new (allocator_for_globals) GlobalRegistrationSiteVector;
@@ -398,7 +398,7 @@
 // We must do this when a shared objects gets dlclosed.
 void __asan_unregister_globals(__asan_global *globals, uptr n) {
   if (!flags()->report_globals) return;
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   for (uptr i = 0; i < n; i++) {
     if (SANITIZER_WINDOWS && globals[i].beg == 0) {
       // Skip globals that look like padding from the MSVC incremental linker.
@@ -424,7 +424,7 @@
   bool strict_init_order = flags()->strict_init_order;
   CHECK(module_name);
   CHECK(asan_inited);
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   if (flags()->report_globals >= 3)
     Printf("DynInitPoison module: %s\n", module_name);
   for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
@@ -448,7 +448,7 @@
       !dynamic_init_globals)
     return;
   CHECK(asan_inited);
-  BlockingMutexLock lock(&mu_for_globals);
+  Lock lock(&mu_for_globals);
   // FIXME: Optionally report that we're unpoisoning globals from a module.
   for (uptr i = 0, n = dynamic_init_globals->size(); i < n; ++i) {
     DynInitGlobal &dyn_g = (*dynamic_init_globals)[i];
diff --git a/compiler-rt/lib/asan/asan_report.cpp b/compiler-rt/lib/asan/asan_report.cpp
--- a/compiler-rt/lib/asan/asan_report.cpp
+++ b/compiler-rt/lib/asan/asan_report.cpp
@@ -32,12 +32,12 @@
 static void (*error_report_callback)(const char*);
 static char *error_message_buffer = nullptr;
 static uptr error_message_buffer_pos = 0;
-static BlockingMutex error_message_buf_mutex(LINKER_INITIALIZED);
+static Mutex error_message_buf_mutex;
 static const unsigned kAsanBuggyPcPoolSize = 25;
 static __sanitizer::atomic_uintptr_t AsanBuggyPcPool[kAsanBuggyPcPoolSize];
 
 void AppendToErrorMessageBuffer(const char *buffer) {
-  BlockingMutexLock l(&error_message_buf_mutex);
+  Lock l(&error_message_buf_mutex);
   if (!error_message_buffer) {
     error_message_buffer =
       (char*)MmapOrDieQuietly(kErrorMessageBufferSize, __func__);
@@ -158,7 +158,7 @@
     // lock that gets aquired during printing.
     InternalMmapVector<char> buffer_copy(kErrorMessageBufferSize);
     {
-      BlockingMutexLock l(&error_message_buf_mutex);
+      Lock l(&error_message_buf_mutex);
       internal_memcpy(buffer_copy.data(),
                       error_message_buffer, kErrorMessageBufferSize);
       // Clear error_message_buffer so that if we find other errors
@@ -490,7 +490,7 @@
 }
 
 void NOINLINE __asan_set_error_report_callback(void (*callback)(const char*)) {
-  BlockingMutexLock l(&error_message_buf_mutex);
+  Lock l(&error_message_buf_mutex);
   error_report_callback = callback;
 }
 
diff --git a/compiler-rt/lib/asan/asan_stats.cpp b/compiler-rt/lib/asan/asan_stats.cpp
--- a/compiler-rt/lib/asan/asan_stats.cpp
+++ b/compiler-rt/lib/asan/asan_stats.cpp
@@ -62,11 +62,11 @@
     dst_ptr[i] += src_ptr[i];
 }
 
-static BlockingMutex print_lock(LINKER_INITIALIZED);
+static Mutex print_lock;
 
 static AsanStats unknown_thread_stats(LINKER_INITIALIZED);
 static AsanStats dead_threads_stats(LINKER_INITIALIZED);
-static BlockingMutex dead_threads_stats_lock(LINKER_INITIALIZED);
+static Mutex dead_threads_stats_lock;
 // Required for malloc_zone_statistics() on OS X. This can't be stored in
 // per-thread AsanStats.
 static uptr max_malloced_memory;
@@ -87,7 +87,7 @@
   }
   stats->MergeFrom(&unknown_thread_stats);
   {
-    BlockingMutexLock lock(&dead_threads_stats_lock);
+    Lock lock(&dead_threads_stats_lock);
     stats->MergeFrom(&dead_threads_stats);
   }
   // This is not very accurate: we may miss allocation peaks that happen
@@ -99,7 +99,7 @@
 }
 
 void FlushToDeadThreadStats(AsanStats *stats) {
-  BlockingMutexLock lock(&dead_threads_stats_lock);
+  Lock lock(&dead_threads_stats_lock);
   dead_threads_stats.MergeFrom(stats);
   stats->Clear();
 }
@@ -122,7 +122,7 @@
   AsanStats stats;
   GetAccumulatedStats(&stats);
   // Use lock to keep reports from mixing up.
-  BlockingMutexLock lock(&print_lock);
+  Lock lock(&print_lock);
   stats.Print();
   StackDepotStats *stack_depot_stats = StackDepotGetStats();
   Printf("Stats: StackDepot: %zd ids; %zdM allocated\n",
diff --git a/compiler-rt/lib/asan/asan_thread.cpp b/compiler-rt/lib/asan/asan_thread.cpp
--- a/compiler-rt/lib/asan/asan_thread.cpp
+++ b/compiler-rt/lib/asan/asan_thread.cpp
@@ -43,11 +43,11 @@
 static ALIGNED(16) char thread_registry_placeholder[sizeof(ThreadRegistry)];
 static ThreadRegistry *asan_thread_registry;
 
-static BlockingMutex mu_for_thread_context(LINKER_INITIALIZED);
+static Mutex mu_for_thread_context;
 static LowLevelAllocator allocator_for_thread_context;
 
 static ThreadContextBase *GetAsanThreadContext(u32 tid) {
-  BlockingMutexLock lock(&mu_for_thread_context);
+  Lock lock(&mu_for_thread_context);
   return new(allocator_for_thread_context) AsanThreadContext(tid);
 }
 
diff --git a/compiler-rt/lib/cfi/cfi.cpp b/compiler-rt/lib/cfi/cfi.cpp
--- a/compiler-rt/lib/cfi/cfi.cpp
+++ b/compiler-rt/lib/cfi/cfi.cpp
@@ -320,7 +320,7 @@
 }
 
 THREADLOCAL int in_loader;
-BlockingMutex shadow_update_lock(LINKER_INITIALIZED);
+Mutex shadow_update_lock;
 
 void EnterLoader() NO_THREAD_SAFETY_ANALYSIS {
   if (in_loader == 0) {
@@ -436,11 +436,11 @@
   return res;
 }
 
-static BlockingMutex interceptor_init_lock(LINKER_INITIALIZED);
+static Mutex interceptor_init_lock;
 static bool interceptors_inited = false;
 
 static void EnsureInterceptorsInitialized() {
-  BlockingMutexLock lock(&interceptor_init_lock);
+  Lock lock(&interceptor_init_lock);
   if (interceptors_inited)
     return;
 
diff --git a/compiler-rt/lib/lsan/lsan_common.cpp b/compiler-rt/lib/lsan/lsan_common.cpp
--- a/compiler-rt/lib/lsan/lsan_common.cpp
+++ b/compiler-rt/lib/lsan/lsan_common.cpp
@@ -30,7 +30,7 @@
 
 // This mutex is used to prevent races between DoLeakCheck and IgnoreObject, and
 // also to protect the global list of root regions.
-BlockingMutex global_mutex(LINKER_INITIALIZED);
+Mutex global_mutex;
 
 Flags lsan_flags;
 
@@ -742,7 +742,7 @@
 bool HasReportedLeaks() { return has_reported_leaks; }
 
 void DoLeakCheck() {
-  BlockingMutexLock l(&global_mutex);
+  Lock l(&global_mutex);
   static bool already_done;
   if (already_done) return;
   already_done = true;
@@ -751,7 +751,7 @@
 }
 
 static int DoRecoverableLeakCheck() {
-  BlockingMutexLock l(&global_mutex);
+  Lock l(&global_mutex);
   bool have_leaks = CheckForLeaks();
   return have_leaks ? 1 : 0;
 }
@@ -954,7 +954,7 @@
     return;
   // Cannot use PointsIntoChunk or LsanMetadata here, since the allocator is not
   // locked.
-  BlockingMutexLock l(&global_mutex);
+  Lock l(&global_mutex);
   IgnoreObjectResult res = IgnoreObjectLocked(p);
   if (res == kIgnoreObjectInvalid)
     VReport(1, "__lsan_ignore_object(): no heap object found at %p", p);
@@ -969,7 +969,7 @@
 SANITIZER_INTERFACE_ATTRIBUTE
 void __lsan_register_root_region(const void *begin, uptr size) {
 #if CAN_SANITIZE_LEAKS
-  BlockingMutexLock l(&global_mutex);
+  Lock l(&global_mutex);
   CHECK(root_regions);
   RootRegion region = {reinterpret_cast<uptr>(begin), size};
   root_regions->push_back(region);
@@ -980,7 +980,7 @@
 SANITIZER_INTERFACE_ATTRIBUTE
 void __lsan_unregister_root_region(const void *begin, uptr size) {
 #if CAN_SANITIZE_LEAKS
-  BlockingMutexLock l(&global_mutex);
+  Lock l(&global_mutex);
   CHECK(root_regions);
   bool removed = false;
   for (uptr i = 0; i < root_regions->size(); i++) {
diff --git a/compiler-rt/lib/memprof/memprof_stats.cpp b/compiler-rt/lib/memprof/memprof_stats.cpp
--- a/compiler-rt/lib/memprof/memprof_stats.cpp
+++ b/compiler-rt/lib/memprof/memprof_stats.cpp
@@ -62,11 +62,11 @@
     dst_ptr[i] += src_ptr[i];
 }
 
-static BlockingMutex print_lock(LINKER_INITIALIZED);
+static Mutex print_lock;
 
 static MemprofStats unknown_thread_stats(LINKER_INITIALIZED);
 static MemprofStats dead_threads_stats(LINKER_INITIALIZED);
-static BlockingMutex dead_threads_stats_lock(LINKER_INITIALIZED);
+static Mutex dead_threads_stats_lock;
 // Required for malloc_zone_statistics() on OS X. This can't be stored in
 // per-thread MemprofStats.
 static uptr max_malloced_memory;
@@ -87,7 +87,7 @@
   }
   stats->MergeFrom(&unknown_thread_stats);
   {
-    BlockingMutexLock lock(&dead_threads_stats_lock);
+    Lock lock(&dead_threads_stats_lock);
     stats->MergeFrom(&dead_threads_stats);
   }
   // This is not very accurate: we may miss allocation peaks that happen
@@ -99,7 +99,7 @@
 }
 
 void FlushToDeadThreadStats(MemprofStats *stats) {
-  BlockingMutexLock lock(&dead_threads_stats_lock);
+  Lock lock(&dead_threads_stats_lock);
   dead_threads_stats.MergeFrom(stats);
   stats->Clear();
 }
@@ -113,7 +113,7 @@
   MemprofStats stats;
   GetAccumulatedStats(&stats);
   // Use lock to keep reports from mixing up.
-  BlockingMutexLock lock(&print_lock);
+  Lock lock(&print_lock);
   stats.Print();
   StackDepotStats *stack_depot_stats = StackDepotGetStats();
   Printf("Stats: StackDepot: %zd ids; %zdM allocated\n",
diff --git a/compiler-rt/lib/memprof/memprof_thread.cpp b/compiler-rt/lib/memprof/memprof_thread.cpp
--- a/compiler-rt/lib/memprof/memprof_thread.cpp
+++ b/compiler-rt/lib/memprof/memprof_thread.cpp
@@ -40,11 +40,11 @@
 static ALIGNED(16) char thread_registry_placeholder[sizeof(ThreadRegistry)];
 static ThreadRegistry *memprof_thread_registry;
 
-static BlockingMutex mu_for_thread_context(LINKER_INITIALIZED);
+static Mutex mu_for_thread_context;
 static LowLevelAllocator allocator_for_thread_context;
 
 static ThreadContextBase *GetMemprofThreadContext(u32 tid) {
-  BlockingMutexLock lock(&mu_for_thread_context);
+  Lock lock(&mu_for_thread_context);
   return new (allocator_for_thread_context) MemprofThreadContext(tid);
 }
 
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_coverage_fuchsia.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_fuchsia.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_coverage_fuchsia.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_coverage_fuchsia.cpp
@@ -51,6 +51,8 @@
 // This class relies on zero-initialization.
 class TracePcGuardController final {
  public:
+  constexpr TracePcGuardController() {}
+
   // For each PC location being tracked, there is a u32 reserved in global
   // data called the "guard".  At startup, we assign each guard slot a
   // unique index into the big results array.  Later during runtime, the
@@ -114,7 +116,7 @@
   // We can always spare the 32G of address space.
   static constexpr size_t MappingSize = sizeof(uptr) << 32;
 
-  BlockingMutex setup_lock_ = BlockingMutex(LINKER_INITIALIZED);
+  Mutex setup_lock_;
   uptr *array_ = nullptr;
   u32 next_index_ = 0;
   zx_handle_t vmo_ = {};
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp b/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
--- a/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
@@ -784,8 +784,8 @@
 void internal_join_thread(void *th) { pthread_join((pthread_t)th, 0); }
 
 #if !SANITIZER_GO
-static BlockingMutex syslog_lock(LINKER_INITIALIZED);
-#endif
+static Mutex syslog_lock;
+#  endif
 
 void WriteOneLineToSyslog(const char *s) {
 #if !SANITIZER_GO
@@ -800,7 +800,7 @@
 
 // buffer to store crash report application information
 static char crashreporter_info_buff[__sanitizer::kErrorMessageBufferSize] = {};
-static BlockingMutex crashreporter_info_mutex(LINKER_INITIALIZED);
+static Mutex crashreporter_info_mutex;
 
 extern "C" {
 // Integrate with crash reporter libraries.
@@ -830,7 +830,7 @@
 }  // extern "C"
 
 static void CRAppendCrashLogMessage(const char *msg) {
-  BlockingMutexLock l(&crashreporter_info_mutex);
+  Lock l(&crashreporter_info_mutex);
   internal_strlcat(crashreporter_info_buff, msg,
                    sizeof(crashreporter_info_buff));
 #if HAVE_CRASHREPORTERCLIENT_H
@@ -874,7 +874,7 @@
   // the reporting thread holds the thread registry mutex, and asl_log waits
   // for GCD to dispatch a new thread, the process will deadlock, because the
   // pthread_create wrapper needs to acquire the lock as well.
-  BlockingMutexLock l(&syslog_lock);
+  Lock l(&syslog_lock);
   if (common_flags()->log_to_syslog)
     WriteToSyslog(buffer);
 
diff --git a/compiler-rt/lib/sanitizer_common/tests/sanitizer_thread_registry_test.cpp b/compiler-rt/lib/sanitizer_common/tests/sanitizer_thread_registry_test.cpp
--- a/compiler-rt/lib/sanitizer_common/tests/sanitizer_thread_registry_test.cpp
+++ b/compiler-rt/lib/sanitizer_common/tests/sanitizer_thread_registry_test.cpp
@@ -19,12 +19,12 @@
 
 namespace __sanitizer {
 
-static BlockingMutex tctx_allocator_lock(LINKER_INITIALIZED);
+static Mutex tctx_allocator_lock;
 static LowLevelAllocator tctx_allocator;
 
 template<typename TCTX>
 static ThreadContextBase *GetThreadContext(u32 tid) {
-  BlockingMutexLock l(&tctx_allocator_lock);
+  Lock l(&tctx_allocator_lock);
   return new(tctx_allocator) TCTX(tid);
 }