diff --git a/make_helpers/unix.mk b/make_helpers/unix.mk
index 545ddfd..d285799 100644
--- a/make_helpers/unix.mk
+++ b/make_helpers/unix.mk
@@ -57,4 +57,7 @@
 	-${Q}rm -rf  "${1}"
     endef
 
+    nul := /dev/null
+
+    which = $(shell which $(1) 2>$(nul))
 endif