diff --git a/src/Make_morph.mak b/src/Make_morph.mak
index 3f896da..87b7e45 100644
--- a/src/Make_morph.mak
+++ b/src/Make_morph.mak
@@ -76,6 +76,7 @@
 	normal.c						\
 	ops.c							\
 	option.c						\
+	optionstr.c						\
 	os_amiga.c						\
 	popupmnu.c						\
 	profiler.c						\