diff --git a/tools/regression_test.sh b/tools/regression_test.sh
index 06ab4c544..72eb8bfab 100755
--- a/tools/regression_test.sh
+++ b/tools/regression_test.sh
@@ -376,7 +376,7 @@ function build_db_bench_and_ldb {
   make clean
   exit_on_error $?
 
-  DEBUG_LEVEL=0 make db_bench ldb -j32
+  DEBUG_LEVEL=0 PORTABLE=1 make db_bench ldb -j32
   exit_on_error $?
 }