* 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>.

diff --git a/ChangeLog b/ChangeLog
index 7a09525a9bfb260d26c55d11672b4efab7527dcc..f782c417f0a7819d572168294e1a4a892e36d212 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2006-06-14  Paul Eggert  <eggert@cs.ucla.edu>
+
+       * 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>.
+
 2006-06-13  Paul Eggert  <eggert@cs.ucla.edu>
 
        * doc/autoconf.texi: Some systematic minor improvements, as

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index a1a12bde10d99ff3de1503d7e4ad5e2ab3133090..2bfd8df184fec942feaccc9c5d44a0f47b7257e8 100644 (file)
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -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
+@code{AC_INIT}, because other Autoconf macros liberally use the
+@command{set} 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
+@samp{$@@}, so if you are writing shell code intended for
+@command{configure} you should not assume that the value of @samp{$@@}
+persists for any length of time.
+
 
 @item $@{10@}
 @cindex positional parameters