diff --git a/opengl/libagl/Android.mk b/opengl/libagl/Android.mk
index a3dff76..99efe4c 100644
--- a/opengl/libagl/Android.mk
+++ b/opengl/libagl/Android.mk
@@ -27,6 +27,11 @@
 	LOCAL_CFLAGS += -fstrict-aliasing
 endif
 
+ifneq ($(TARGET_SIMULATOR),true)
+    # we need to access the private Bionic header <bionic_tls.h>
+    LOCAL_CFLAGS += -I$(LOCAL_PATH)/../../../../bionic/libc/private
+endif
+
 LOCAL_SHARED_LIBRARIES := libcutils libutils libpixelflinger
 LOCAL_LDLIBS := -lpthread -ldl
 LOCAL_MODULE:= libagl