add missing comm.o rule
diff --git a/coreutils/Makefile.in b/coreutils/Makefile.in
index 7c5b498..dd6d2fa 100644
--- a/coreutils/Makefile.in
+++ b/coreutils/Makefile.in
@@ -32,6 +32,7 @@
 COREUTILS-$(CONFIG_CHOWN)     += chown.o
 COREUTILS-$(CONFIG_CHROOT)    += chroot.o
 COREUTILS-$(CONFIG_CMP)       += cmp.o
+COREUTILS-$(CONFIG_COMM)      += comm.o
 COREUTILS-$(CONFIG_CP)        += cp.o
 COREUTILS-$(CONFIG_CUT)       += cut.o
 COREUTILS-$(CONFIG_DATE)      += date.o