diff --git a/common.mk b/common.mk
index e3c92fa1..23ac8e34 100644
--- a/common.mk
+++ b/common.mk
@@ -2,8 +2,6 @@ UNAME=$(shell uname)
 DEBUG=1
 COVERAGE=0
 INSTALL=install
-FLEX=flex
-BISON=bison
 ifndef PREFIX
   PREFIX=/usr
 endif