diff --git a/arch/um/Makefile b/arch/um/Makefile
index 01b97c19a8ba99da4a07db8194397b1611b265e6..dbeab15e7bb7c160db7dda887a4c9d14982f742c 100644
--- a/arch/um/Makefile
+++ b/arch/um/Makefile
@@ -77,10 +77,7 @@ include $(srctree)/$(ARCH_DIR)/Makefile-os-$(OS)
 KERNEL_DEFINES = $(strip -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \
 			 -Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES))
 KBUILD_CFLAGS += $(KERNEL_DEFINES)
-# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
-# a lot more stack due to the lack of sharing of stacklots:
-KBUILD_CFLAGS += $(shell if [ $(call cc-version) -lt 0400 ] ; then \
-			echo $(call cc-option,-fno-unit-at-a-time); fi ;)
+KBUILD_CFLAGS += $(call cc-option,-fno-unit-at-a-time,)
 
 PHONY += linux