diff --git a/Makefile b/Makefile
index f5d45f5fa97359bc7f7f0c963f738bbb05dbfee0..c850ec775337ff637294ff5decb9f8c20c3e61cd 100644
--- a/Makefile
+++ b/Makefile
@@ -179,7 +179,7 @@ DEFINES += $(DEFINES_$(CONFIG)) INSTALL_PREFIX=\"$(prefix)\"
 LDFLAGS += $(LDFLAGS_$(CONFIG))
 
 ifdef EXTRA_DEFINES
-DEFINES += EXTRA_DEFINES
+DEFINES += $(EXTRA_DEFINES)
 endif
 
 CFLAGS += -std=c89 -pedantic