diff --git a/libs/minikin/Android.mk b/libs/minikin/Android.mk
index 4c945a60c9c8b7085a96bb3dfc123f31e586febd..b2e1dc8293687df5c580bddacd6869405a8b3407 100644
--- a/libs/minikin/Android.mk
+++ b/libs/minikin/Android.mk
@@ -47,11 +47,18 @@ minikin_shared_libraries := \
     libicuuc \
     libutils
 
+ifneq (,$(filter userdebug eng, $(TARGET_BUILD_VARIANT)))
+# Enable race detection on eng and userdebug build.
+enable_race_detection := -DENABLE_RACE_DETECTION
+else
+enable_race_detection :=
+endif
+
 LOCAL_MODULE := libminikin
 LOCAL_EXPORT_C_INCLUDE_DIRS := frameworks/minikin/include
 LOCAL_SRC_FILES := $(minikin_src_files)
 LOCAL_C_INCLUDES := $(minikin_c_includes)
-LOCAL_CPPFLAGS += -Werror -Wall -Wextra
+LOCAL_CPPFLAGS += -Werror -Wall -Wextra $(enable_race_detection)
 LOCAL_SHARED_LIBRARIES := $(minikin_shared_libraries)
 
 include $(BUILD_SHARED_LIBRARY)
@@ -63,7 +70,7 @@ LOCAL_MODULE_TAGS := optional
 LOCAL_EXPORT_C_INCLUDE_DIRS := frameworks/minikin/include
 LOCAL_SRC_FILES := $(minikin_src_files)
 LOCAL_C_INCLUDES := $(minikin_c_includes)
-LOCAL_CPPFLAGS += -Werror -Wall -Wextra
+LOCAL_CPPFLAGS += -Werror -Wall -Wextra $(enable_race_detection)
 LOCAL_SHARED_LIBRARIES := $(minikin_shared_libraries)
 
 include $(BUILD_STATIC_LIBRARY)
@@ -76,7 +83,7 @@ LOCAL_MODULE := libminikin_host
 LOCAL_MODULE_TAGS := optional
 LOCAL_EXPORT_C_INCLUDE_DIRS := frameworks/minikin/include
 LOCAL_C_INCLUDES := $(minikin_c_includes)
-LOCAL_CPPFLAGS += -Werror -Wall -Wextra
+LOCAL_CPPFLAGS += -Werror -Wall -Wextra $(enable_race_detection)
 LOCAL_SHARED_LIBRARIES := liblog libicuuc-host
 
 LOCAL_SRC_FILES := Hyphenator.cpp
diff --git a/libs/minikin/FontCollection.cpp b/libs/minikin/FontCollection.cpp
index bba2ef95359f1c6cd44ebe20ce172016c71b8659..529b5c03a34c01759db647d658ea7d7d8a782c5e 100644
--- a/libs/minikin/FontCollection.cpp
+++ b/libs/minikin/FontCollection.cpp
@@ -223,6 +223,7 @@ bool FontCollection::hasVariationSelector(uint32_t baseCodepoint,
     // Currently mRanges can not be used here since it isn't aware of the variation sequence.
     // TODO: Use mRanges for narrowing down the search range.
     for (size_t i = 0; i < mFamilies.size(); i++) {
+        AutoMutex _l(gMinikinLock);
         if (mFamilies[i]->hasVariationSelector(baseCodepoint, variationSelector)) {
           return true;
         }
diff --git a/libs/minikin/MinikinInternal.cpp b/libs/minikin/MinikinInternal.cpp
index 5a21ef9862c5fd7007c60c7b28dd0e4a0b6b5c0d..c2aa01ac1988ae8713bc111f204a9f9192cf9e81 100644
--- a/libs/minikin/MinikinInternal.cpp
+++ b/libs/minikin/MinikinInternal.cpp
@@ -25,7 +25,9 @@ namespace android {
 Mutex gMinikinLock;
 
 void assertMinikinLocked() {
-    LOG_FATAL_IF(gMinikinLock.tryLock() == 0);
+#ifdef ENABLE_RACE_DETECTION
+    LOG_ALWAYS_FATAL_IF(gMinikinLock.tryLock() == 0);
+#endif
 }
 
 }