diff --git a/makefiles/modules.inc.mk b/makefiles/modules.inc.mk
index 9d2f289bae..f02218f35d 100644
--- a/makefiles/modules.inc.mk
+++ b/makefiles/modules.inc.mk
@@ -1,11 +1,11 @@
 _ALLMODULES = $(sort $(USEMODULE) $(USEPKG))
 
+# Define MODULE_MODULE_NAME preprocessor macros for all modules.
 ED = $(addprefix MODULE_,$(_ALLMODULES))
 EXTDEFINES = $(addprefix -D,$(shell echo '$(ED)' | tr 'a-z-' 'A-Z_'))
+CFLAGS += $(EXTDEFINES)
 
 # filter "pseudomodules" from "real modules", but not "no_pseudomodules"
 NO_PSEUDOMODULES := $(filter $(NO_PSEUDOMODULES), $(_ALLMODULES))
 REALMODULES = $(filter-out $(PSEUDOMODULES), $(_ALLMODULES)) $(NO_PSEUDOMODULES)
 BASELIBS += $(REALMODULES:%=$(BINDIR)/%.a)
-
-CFLAGS += $(EXTDEFINES)