From b768fb2197ca8bd75299daed87ff09167eb527a1 Mon Sep 17 00:00:00 2001 From: Bruno Haible Date: Tue, 8 Jul 2008 12:18:03 +0200 Subject: [PATCH] Update comments. --- ChangeLog | 5 +++++ m4/onceonly.m4 | 15 +++++++++------ 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/ChangeLog b/ChangeLog index 6c5f5227d2..06100dea6b 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2008-07-08 Bruno Haible + + * m4/onceonly.m4: Update comments. + Reported by Ben Pfaff . + 2008-07-04 Jim Meyering * users.txt: Add vc-dwim. diff --git a/m4/onceonly.m4 b/m4/onceonly.m4 index 2bf1590d59..108cd6c1a5 100644 --- a/m4/onceonly.m4 +++ b/m4/onceonly.m4 @@ -1,4 +1,4 @@ -# onceonly.m4 serial 5 +# onceonly.m4 serial 6 dnl Copyright (C) 2002-2003, 2005-2006, 2008 Free Software Foundation, Inc. dnl This file is free software, distributed under the terms of the GNU dnl General Public License. As a special exception to the GNU General @@ -21,13 +21,16 @@ dnl inside an AC_DEFUNed function, the gl_CHECK_HEADERS macro call expands to dnl empty, and the check will be inserted before the body of the AC_DEFUNed dnl function. -dnl This is like onceonly.m4, except that it uses diversions to named sections -dnl DEFAULTS and INIT_PREPARE in order to check all requested headers at once, -dnl thus reducing the size of 'configure'. Works with autoconf-2.57. The -dnl size reduction is ca. 9%. +dnl The original code implemented AC_CHECK_HEADERS_ONCE and AC_CHECK_FUNCS_ONCE +dnl in terms of AC_DEFUN and AC_REQUIRE. This implementation uses diversions to +dnl named sections DEFAULTS and INIT_PREPARE in order to check all requested +dnl headers at once, thus reducing the size of 'configure'. It is known to work +dnl with autoconf 2.57..2.62 at least . The size reduction is ca. 9%. dnl Autoconf version 2.59 plus gnulib is required; this file is not needed -dnl with Autoconf 2.60 or greater. +dnl with Autoconf 2.60 or greater. But note that autoconf's implementation of +dnl AC_CHECK_DECLS_ONCE expects a comma-separated list of symbols as first +dnl argument! AC_PREREQ([2.59]) # AC_CHECK_HEADERS_ONCE(HEADER1 HEADER2 ...) is a once-only variant of -- 2.30.2