(_AS_LINENO_PREPARE): Unset ENV and BASH_ENV when reinvoking the

shell, to work around problems with installers who put strange things
like "cd" commands in their environments.

diff --git a/lib/m4sugar/m4sh.m4 b/lib/m4sugar/m4sh.m4
index 0275fe3f252d351f556c1712d39e8327229dec34..27a27e481f15fd5c4a1b288e3e27c3dff9021878 100644 (file)
--- a/lib/m4sugar/m4sh.m4
+++ b/lib/m4sugar/m4sh.m4
@@ -507,6 +507,8 @@ m4_define([_AS_LINENO_PREPARE],
         case $as_dir in
         /*)
           if ("$as_dir/$as_base" -c '_AS_LINENO_WORKS') 2>/dev/null; then
+            AS_UNSET(BASH_ENV)
+            AS_UNSET(ENV)
             CONFIG_SHELL=$as_dir/$as_base
             export CONFIG_SHELL
             exec "$CONFIG_SHELL" "$[0]" ${1+"$[@]"}