diff --git a/Makefile b/Makefile
index a46c1aeed8..77cb8fa294 100644
--- a/Makefile
+++ b/Makefile
@@ -562,10 +562,6 @@ else
 KBUILD_CFLAGS	+= -O2
 endif
 
-ifdef BUILD_TAG
-KBUILD_CFLAGS += -DBUILD_TAG='"$(BUILD_TAG)"'
-endif
-
 KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
 KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks)
 
diff --git a/lib/Makefile b/lib/Makefile
index dd36f25b2a..1e21bcc4c7 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -67,6 +67,7 @@ obj-$(CONFIG_ADDR_MAP) += addr_map.o
 obj-y += hashtable.o
 obj-y += errno.o
 obj-y += display_options.o
+CFLAGS_display_options.o := $(if $(BUILD_TAG),-DBUILD_TAG='"$(BUILD_TAG)"')
 obj-$(CONFIG_BCH) += bch.o
 obj-y += crc32.o
 obj-y += ctype.o