diff --git a/core/host_test_internal.mk b/core/host_test_internal.mk
index 426c400..691468d 100644
--- a/core/host_test_internal.mk
+++ b/core/host_test_internal.mk
@@ -2,7 +2,14 @@
 ## Shared definitions for all host test compilations.
 #####################################################
 
-LOCAL_CFLAGS += -DGTEST_OS_LINUX -DGTEST_HAS_STD_STRING -O0 -g
+ifeq ($(HOST_OS),windows)
+LOCAL_CFLAGS += -DGTEST_OS_WINDOWS
+else
+LOCAL_CFLAGS += -DGTEST_OS_LINUX
+LOCAL_LDLIBS += -lpthread
+endif
+
+LOCAL_CFLAGS += -DGTEST_HAS_STD_STRING -O0 -g
 LOCAL_C_INCLUDES +=  external/gtest/include
 
 ifneq ($(filter libc++,$(LOCAL_SHARED_LIBRARIES)),)
@@ -12,4 +19,3 @@
 LOCAL_SHARED_LIBRARIES +=
 endif
 
-LOCAL_LDLIBS += -lpthread