diff --git a/core/Makefile b/core/Makefile
index c35f744..410fa16 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -124,7 +124,7 @@
   $(error BUILD_FINGERPRINT cannot contain spaces: "$(BUILD_FINGERPRINT)")
 endif
 
-$(shell echo $(BUILD_FINGERPRINT) > $(PRODUCT_OUT)/build_fingerprint.txt)
+$(shell mkdir -p $(PRODUCT_OUT) && echo $(BUILD_FINGERPRINT) > $(PRODUCT_OUT)/build_fingerprint.txt)
 BUILD_FINGERPRINT_FROM_FILE := $$(cat $(PRODUCT_OUT)/build_fingerprint.txt)
 
 # The string used to uniquely identify the system build; used by the OTA server.
diff --git a/core/main.mk b/core/main.mk
index 7f22d76..f9b9d95 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -96,7 +96,7 @@
 # Write the build number to a file so it can be read back in
 # without changing the command line every time.  Avoids rebuilds
 # when using ninja.
-$(shell echo -n $(BUILD_NUMBER) > $(OUT_DIR)/build_number.txt)
+$(shell mkdir -p $(OUT_DIR) && echo -n $(BUILD_NUMBER) > $(OUT_DIR)/build_number.txt)
 BUILD_NUMBER_FROM_FILE := $$(cat $(OUT_DIR)/build_number.txt)
 
 # CTS-specific config.