diff --git a/kernel/Makefile b/kernel/Makefile
index ff1c11d..58908f9 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -12,6 +12,9 @@
 
 obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o
 obj-$(CONFIG_FUTEX) += futex.o
+ifeq ($(CONFIG_COMPAT),y)
+obj-$(CONFIG_FUTEX) += futex_compat.o
+endif
 obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
 obj-$(CONFIG_SMP) += cpu.o spinlock.o
 obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o