diff --git a/tools/buildgen/generate_projects.sh b/tools/buildgen/generate_projects.sh
index c2e88f77938..2e0636fcbed 100755
--- a/tools/buildgen/generate_projects.sh
+++ b/tools/buildgen/generate_projects.sh
@@ -32,7 +32,7 @@ for dir in . ; do
     data=`for i in $json_files; do echo -n "-d $i "; done`
     if [ $TEST == true ] ; then
       actual_out=$out
-      out=`mktemp`
+      out=`mktemp /tmp/gentXXXXXX`
     fi
     $mako_renderer $plugins $data -o $out $file
     if [ $TEST == true ] ; then