diff --git a/boot/barebox/barebox.mk b/boot/barebox/barebox.mk
index 90be8c1ecc..a0cfaffe09 100644
--- a/boot/barebox/barebox.mk
+++ b/boot/barebox/barebox.mk
@@ -74,11 +74,11 @@ endif
 $(1)_MAKE_FLAGS = ARCH=$$($(1)_ARCH) CROSS_COMPILE="$$(TARGET_CROSS)"
 $(1)_MAKE_ENV = $$(TARGET_MAKE_ENV)
 
-ifeq ($(BR2_REPRODUCIBLE),y)
+ifeq ($$(BR2_REPRODUCIBLE),y)
 $(1)_MAKE_ENV += \
 	KBUILD_BUILD_USER=buildroot \
 	KBUILD_BUILD_HOST=buildroot \
-	KBUILD_BUILD_TIMESTAMP="$(shell LC_ALL=C date -d @$(SOURCE_DATE_EPOCH))"
+	KBUILD_BUILD_TIMESTAMP="$$(shell LC_ALL=C date -d @$(SOURCE_DATE_EPOCH))"
 endif
 
 ifeq ($$(BR2_TARGET_$(1)_USE_DEFCONFIG),y)