diff --git a/src/check_bison_ver.sh b/src/check_bison_ver.sh
index 691d15df..c186a378 100755
--- a/src/check_bison_ver.sh
+++ b/src/check_bison_ver.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 bison -V | awk -v major="$1" -v minor="$2" '
 /^bison.*[0-9]+(\.[0-9]+)(\.[0-9]+)?$/ {
 	match($0, /[0-9]+(\.[0-9]+)(\.[0-9]+)?$/);
diff --git a/test/asm/test.sh b/test/asm/test.sh
index 90b02add..4d06356d 100755
--- a/test/asm/test.sh
+++ b/test/asm/test.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 
 export LC_ALL=C
 
diff --git a/test/asm/update-refs.sh b/test/asm/update-refs.sh
index b8b22a19..192ff602 100755
--- a/test/asm/update-refs.sh
+++ b/test/asm/update-refs.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env bash
 fname=$(mktemp)
 
 for i in *.asm; do