diff --git a/builder.sh b/builder.sh
index bdd843d..eabde76 100755
--- a/builder.sh
+++ b/builder.sh
@@ -20,7 +20,7 @@ mv tcl8.5.9-linux-x86_64 tcl
 tar xvfz tcl8.5.9-linux-x86_64-threaded.tar.gz
 mv tcl8.5.9-linux-x86_64-threaded tcl-threaded
 
-tcsh ./config  Linux-x86_64-g++   --charm-arch multicore-linux64 
+tcsh -f ./config  Linux-x86_64-g++   --charm-arch multicore-linux64
 cd Linux-x86_64-g++
 make
 rm -rf obj