diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index b689df8..e689bad 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -764,6 +764,7 @@
 	$(OUTDIR)/syntax.o \
 	$(OUTDIR)/tag.o \
 	$(OUTDIR)/term.o \
+	$(OUTDIR)/testing.o \
 	$(OUTDIR)/textprop.o \
 	$(OUTDIR)/ui.o \
 	$(OUTDIR)/undo.o \