Hello Ralf,
I asked you:
> > Are you willing to prepare another patch and do these two doc
> > enhancements?
you did it. Though I'm not going to use it directly, it helped me
co make my mind. So your work wasn't in vain, though it might seem so.
;-)
> +Since they have to appear before @file{config.status}
> +is created, they may be called no later than in an argument to
> [EMAIL PROTECTED]
This formulation has two problems:
1) Many users would not understand what the "no later" means.
They see the ordering in configure.ac by their own eyes, but they cannot
see the final ordering in configure as clearly as we do.
2) Though there are sometimes reasons to call AC_CONFIG_FOOS
from AC_CONFIG_COMMANDS_PRE, it's not usual. So we shouldn't mention
AC_CONFIG_COMMANDS_PRE here.
I modified your latest doc patch, merged it with the previous one, and
I'm attaching the result here.
If there are no comments, I'll commit after a few days.
Have a nice day,
Stepan
2005-08-16 Ralf Wildenhues <[EMAIL PROTECTED]>,
Stepan Kasal <[EMAIL PROTECTED]>
* lib/autoconf/status.m4 (_AC_CONFIG_REGISTER_DEST): When the
first header appears, define AH_HEADER.
* doc/autoconf.texi (Configuration Headers): Document AH_HEADER.
Update limitations about when to call AC_CONFIG_HEADERS.
(Configuration Commands): Document that AC_CONFIG_COMMANDS_PRE
parameter can call AC_SUBST, AC_DEFINE, or AC_CONFIG_FOOS; explain
that AC_CONFIG_COMMANDS_PRE and AC_CONFIG_COMMANDS_POST are not
``Configuration Actions''; fix their index entries.
Index: doc/autoconf.texi
===================================================================
RCS file: /cvsroot/autoconf/autoconf/doc/autoconf.texi,v
retrieving revision 1.925
diff -u -r1.925 autoconf.texi
--- doc/autoconf.texi 6 Jul 2005 21:39:31 -0000 1.925
+++ doc/autoconf.texi 16 Aug 2005 09:59:21 -0000
@@ -2648,8 +2648,8 @@
operating systems. As an alternative to passing @option{-D} options to
the compiler, @command{configure} scripts can create a C header file
containing @samp{#define} directives. The @code{AC_CONFIG_HEADERS}
-macro selects this kind of output. It should be called right after
[EMAIL PROTECTED]
+macro selects this kind of output. Though it can be called anywhere in
[EMAIL PROTECTED], it is customary to call it right after @code{AC_INIT}.
The package should @samp{#include} the configuration header file before
any other header files, to prevent inconsistencies in declarations (for
@@ -2697,6 +2697,19 @@
to prepend and/or append boilerplate to the file.
@end defmac
[EMAIL PROTECTED] AH_HEADER
+This macro is defined as the name of the first declared config header
+and undefined if no config headers have been declared up to this point.
+A third-party macro may, for example, require use of a config header
+without invoking AC_CONFIG_HEADERS twice like this:
+
[EMAIL PROTECTED]
+AC_CONFIG_COMMANDS_PRE(
+ [m4_ifndef([AH_HEADER], [AC_CONFIG_HEADERS([config.h])])])
[EMAIL PROTECTED] example
+
[EMAIL PROTECTED] defmac
+
@xref{Configuration Actions}, for more details on @var{header}.
@menu
@@ -2970,13 +2983,23 @@
@end example
@end defmac
+The following two macros look similar, but in fact they are not of the same
+breed: they are executed directly by @file{configure}, so you cannot use
[EMAIL PROTECTED] to re-run them.
+
[EMAIL PROTECTED] Yet it is good to leave them here. The user sees them
together and
[EMAIL PROTECTED] decides which best fits their needs.
+
@defmac AC_CONFIG_COMMANDS_PRE (@var{cmds})
[EMAIL PROTECTED]
[EMAIL PROTECTED]
Execute the @var{cmds} right before creating @file{config.status}.
+
+This macro presents the last opportunity to call @code{AC_SUBST},
[EMAIL PROTECTED], or @code{AC_CONFIG_FOOS} macros.
@end defmac
@defmac AC_CONFIG_COMMANDS_POST (@var{cmds})
[EMAIL PROTECTED]
[EMAIL PROTECTED]
Execute the @var{cmds} right after creating @file{config.status}.
@end defmac
Index: lib/autoconf/status.m4
===================================================================
RCS file: /cvsroot/autoconf/autoconf/lib/autoconf/status.m4,v
retrieving revision 1.73
diff -u -r1.73 status.m4
--- lib/autoconf/status.m4 16 Aug 2005 09:11:06 -0000 1.73
+++ lib/autoconf/status.m4 16 Aug 2005 09:59:21 -0000
@@ -258,9 +258,14 @@
# With CONFIG_LINKS, reject DEST=., because it is makes it hard for
./config.status
# to guess the links to establish (`./config.status .').
#
+# Save the name of the first config header to AH_HEADER.
+#
m4_define([_AC_CONFIG_REGISTER_DEST],
[_AC_CONFIG_UNIQUE([$1], [$3])dnl
-m4_if([$1 $3], [LINKS .], [AC_FATAL([invalid destination of a config link:
`.'])])dnl
+m4_if([$1 $3], [LINKS .],
+ [AC_FATAL([invalid destination of a config link: `.'])])dnl
+m4_if([$1], [HEADERS],
+ [m4_define_default([AH_HEADER], [$3])])dnl
dnl
dnl Recognize TAG as an argument to config.status:
dnl
