Quote $OLDPWD in doc

Problem reported by Florian Weimer in:
https://lists.gnu.org/r/autoconf/2025-07/msg00008.html

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index c6b23c78e801c8ca296c9900e063a34674038652..ec7c48c7b23751fb818da063b2389e477077ad5c 100644 (file)
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -17880,7 +17880,7 @@ avoid it for the same reason they avoid @option{-P}.
 @evindex PWD
 POSIX says that a successful @command{cd} updates the values of the
 @env{OLDPWD} and @env{PWD} variables, and that @command{cd -} acts like
-@command{cd $OLDPWD}.  Older shells, such as Solaris 10
+@command{cd "$OLDPWD"}.  Older shells, such as Solaris 10
 @command{/bin/sh}, do not support this and portable scripts should not
 rely on it.