--- m4-1.4.19/configure.vanilla	2023-02-02 00:03:20.157997261 +0100
+++ m4-1.4.19/configure	2023-02-02 00:03:49.898000548 +0100
@@ -1,4 +1,4 @@
-#! /bin/sh
+#! /bin/bash
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.71 for GNU M4 1.4.19.
 #