Ben Pfaff <[EMAIL PROTECTED]> writes:
> In the long term, I suspect that the Autoconf macros in the
> apr-util package should be fixed, and that autoconf-doc should
> document that $@ may be changed by some macros.
I've done the latter by installing the patch at the end of this
message into Autoconf CVS.
> In the short term, I'm willing to help out, if necessary, by putting
> some kind of Debian-specific patch that saves and restores the
> positional parameters (if indeed there's a way to do that) around
> AC_CANONICAL_SYSTEM.
I don't know of any portable, reliable way to do it in general,
but you can approximate it by doing something like this:
# Save "$@".
args=
for arg
do
case $arg in
*\'*) arg=`echo "$arg" | sed "s/'/'\\\\\\\\''/g"`;;
esac
args="$args '$arg'"
done
# Restore "$@".
eval set x $args
shift
But even this isn't correct in general, e.g., it mishandles args
containing backslashes, or equal to '-n', or with trailing newlines.
Here's the patch I installed.
2006-06-14 Paul Eggert <[EMAIL PROTECTED]>
* doc/autoconf.texi (Initializing configure, Shell Substitutions):
Warn about $@ not persisting. Problem reported by Julien Danjou in
<http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=372179>.
--- doc/autoconf.texi 14 Jun 2006 05:14:09 -0000 1.1044
+++ doc/autoconf.texi 14 Jun 2006 19:11:21 -0000
@@ -1747,6 +1747,14 @@ Exactly @var{bug-report}.
@end table
@end defmac
+If your @command{configure} script does its own option processing, it
+should inspect @samp{$@@} or @samp{$*} immediately after calling
[EMAIL PROTECTED], because other Autoconf macros liberally use the
[EMAIL PROTECTED] command to process strings, and this has the side effect
+of updating @samp{$@@} and @samp{$*}. However, we suggest that you use
+standard macros like @code{AC_ARG_ENABLE} instead of attempting to
+implement your own option processing. @xref{Site Configuration}.
+
@node Notices
@section Notices in @command{configure}
@@ -11297,6 +11305,11 @@ case $# in
esac
@end example
+Autocoonf macros often use the @command{set} command to update
[EMAIL PROTECTED]@@}, so if you are writing shell code intended for
[EMAIL PROTECTED] you should not assume that the value of @samp{$@@}
+persists for any length of time.
+
@item [EMAIL PROTECTED]@}
@cindex positional parameters
