minor tidy-up to configury.
diff --git a/test/autogen.sh b/test/autogen.sh
index 988d417..f1716a5 100755
--- a/test/autogen.sh
+++ b/test/autogen.sh
@@ -1,11 +1,9 @@
#!/bin/sh
-cp acinclude.m4 aclocal.m4
+set -e
-if test "$AUTOCONF"x = x; then
- AUTOCONF=autoconf
-fi
+cp acinclude.m4 aclocal.m4
-$AUTOCONF || exit 1
+"${AUTOCONF:-autoconf}"
rm aclocal.m4
rm -rf autom4te.cache