diff --git a/compiler-rt/lib/scudo/standalone/allocator_config.h b/compiler-rt/lib/scudo/standalone/allocator_config.h
--- a/compiler-rt/lib/scudo/standalone/allocator_config.h
+++ b/compiler-rt/lib/scudo/standalone/allocator_config.h
@@ -60,7 +60,7 @@
 
 struct DefaultConfig {
   using SizeClassMap = DefaultSizeClassMap;
-  static const bool MaySupportMemoryTagging = false;
+  static const bool MaySupportMemoryTagging = true;
 
 #if SCUDO_CAN_USE_PRIMARY64
   typedef SizeClassAllocator64<DefaultConfig> Primary;
@@ -87,7 +87,6 @@
 
   template <class A> using TSDRegistryT = TSDRegistryExT<A>; // Exclusive
 };
-
 struct AndroidConfig {
   using SizeClassMap = AndroidSizeClassMap;
   static const bool MaySupportMemoryTagging = true;
diff --git a/compiler-rt/lib/scudo/standalone/tests/scudo_unit_test_main.cpp b/compiler-rt/lib/scudo/standalone/tests/scudo_unit_test_main.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/scudo_unit_test_main.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/scudo_unit_test_main.cpp
@@ -17,12 +17,28 @@
 #define DEALLOC_TYPE_MISMATCH "true"
 #endif
 
+static void EnableMemoryTaggingIfSupported() {
+  if (!scudo::archSupportsMemoryTagging())
+    return;
+  static bool Done = []() {
+    if (!scudo::systemDetectsMemoryTagFaultsTestOnly())
+      scudo::enableSystemMemoryTaggingTestOnly();
+    return true;
+  }();
+  (void)Done;
+}
+
 // This allows us to turn on/off a Quarantine for specific tests. The Quarantine
 // parameters are on the low end, to avoid having to loop excessively in some
 // tests.
 bool UseQuarantine = true;
 extern "C" __attribute__((visibility("default"))) const char *
 __scudo_default_options() {
+  // Wrappers tests initialize global allocator early, before the main(). We
+  // need to have Memory Tagging enabled before that happeng or allocator will
+  // dissable the feature at all. This code is called by Allocator::init() early
+  // enough to achieve that.
+  EnableMemoryTaggingIfSupported();
   if (!UseQuarantine)
     return "dealloc_type_mismatch=" DEALLOC_TYPE_MISMATCH;
   return "quarantine_size_kb=256:thread_local_quarantine_size_kb=128:"
@@ -34,8 +50,7 @@
 // for Fuchsia builds.
 #if !SCUDO_FUCHSIA
 int main(int argc, char **argv) {
-  if (scudo::archSupportsMemoryTagging())
-    scudo::enableSystemMemoryTaggingTestOnly();
+  EnableMemoryTaggingIfSupported();
   testing::InitGoogleTest(&argc, argv);
   return RUN_ALL_TESTS();
 }
diff --git a/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp b/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
--- a/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
+++ b/compiler-rt/lib/scudo/standalone/tests/wrappers_cpp_test.cpp
@@ -6,6 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "memtag.h"
 #include "tests/scudo_unit_test.h"
 
 #include <atomic>
@@ -107,6 +108,11 @@
 }
 
 TEST(ScudoWrappersCppTest, ThreadedNew) {
+#if !SCUDO_ANDROID
+  // TODO: Investigate why libc sometimes crashes with tag missmatch in
+  // __pthread_clockjoin_ex.
+  scudo::ScopedDisableMemoryTagChecks NoTags;
+#endif
   Ready = false;
   std::thread Threads[32];
   for (size_t I = 0U; I < sizeof(Threads) / sizeof(Threads[0]); I++)