+# Copyright © 2023 Nick Bowler
+#
+# Compatibility helper for Autotest test suites. This should be included
+# before expanding AT_INIT
+#
+# License WTFPL2: Do What The Fuck You Want To Public License, version 2.
+# This is free software: you are free to do what the fuck you want to.
+# There is NO WARRANTY, to the extent permitted by law.
+
+# Redefine AT_INIT to work around nonportable constructs in current
+# (as of 2023) Autoconf releases:
+#
+# - In a shell function, redirections on : are not correctly handled
+# by Solaris /bin/sh. See the following Autoconf patch for details:
+#
+# https://lists.gnu.org/archive/html/autoconf-patches/2021-03/msg00000.html
+
+m4_define([AT_INIT],
+ m4_bpatsubst(m4_dquote(m4_defn([AT_INIT])),
+ [^\( *\)\(: >"\$at_stdout".*$\)], [\1eval '\2']))