diff --git a/core/config.mk b/core/config.mk
index 676bd64..b34bd2b 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -144,6 +144,8 @@
 # Here since this file is included by envsetup as well as during build.
 include $(BUILD_SYSTEM)/math.mk
 
+include $(BUILD_SYSTEM)/strings.mk
+
 # Various mappings to avoid hard-coding paths all over the place
 include $(BUILD_SYSTEM)/pathmap.mk