diff --git a/core/board_config.mk b/core/board_config.mk
index 2580a33..7e55bfc 100644
--- a/core/board_config.mk
+++ b/core/board_config.mk
@@ -181,7 +181,7 @@
 # Sanity check to warn about likely cryptic errors later in the build.
 ifeq ($(TARGET_IS_64_BIT),true)
   ifeq (,$(filter true false,$(TARGET_SUPPORTS_64_BIT_APPS)))
-    $(warning Building a 32-bit-app-only product on a 64-bit device. \
+    $(error Building a 32-bit-app-only product on a 64-bit device. \
       If this is intentional, set TARGET_SUPPORTS_64_BIT_APPS := false)
   endif
 endif