diff --git a/arch/sim/src/Makefile b/arch/sim/src/Makefile
index 63126fb625d..bb44ab705f4 100644
--- a/arch/sim/src/Makefile
+++ b/arch/sim/src/Makefile
@@ -39,12 +39,13 @@ CFLAGS += -I$(TOPDIR)/sched
 
 ASRCS = up_setjmp.S
 AOBJS = $(ASRCS:.S=$(OBJEXT))
-CSRCS = up_initialize.c up_idle.c up_interruptcontext.c \
-		up_initialstate.c up_createstack.c up_usestack.c \
-		up_releasestack.c  up_unblocktask.c up_blocktask.c \
-		up_releasepending.c up_reprioritizertr.c \
-		up_exit.c up_schedulesigaction.c up_allocateheap.c \
-		up_devconsole.c
+
+CSRCS  = up_initialize.c up_idle.c up_interruptcontext.c up_initialstate.c
+CSRCS += up_createstack.c up_usestack.c up_releasestack.c up_stackframe.c
+CSRCS += up_unblocktask.c up_blocktask.c up_releasepending.c
+CSRCS += up_reprioritizertr.c up_exit.c up_schedulesigaction.c
+CSRCS += up_allocateheap.c up_devconsole.c
+
 HOSTSRCS = up_stdio.c up_hostusleep.c
 
 ifeq ($(CONFIG_SCHED_TICKLESS),y)