autoconf warning in gl_EARLY

[Denis Laroche]

I'm not sure if the post should be sent to the autoconf mailing list
instead. I see the following warnings from gl_EARLY when running
autoconf (version 2.69):

configure.ac:42: warning: AC_RUN_IFELSE was called before
AC_USE_SYSTEM_EXTENSIONS
../../lib/autoconf/specific.m4:314: AC_GNU_SOURCE is expanded from...
m4/gnulib-comp.m4:34: gl_EARLY is expanded from...
configure.ac:42: the top level

The version of gnulib is 0.1.147-b1b4ba. Looking at the definition of
gl_EARLY, it's expanding macro gl_USE_SYSTEM_EXTENSIONS. The
documenation of this macro says that its purpose is to avoid those
warnings. The rest of the message shows the beginning of configure.ac.

Thanks in advance!

AC_PREREQ([2.69])

AC_INIT([lvibs], [0.1.0], address@hidden)
AC_CONFIG_AUX_DIR([build-aux])
AC_CONFIG_MACRO_DIR([m4])
AC_CONFIG_SRCDIR([src/lvibs.c])

AM_INIT_AUTOMAKE([1.11 color-tests subdir-objects -Wall])
LT_PREREQ([2.2])
AM_PROG_AR
LT_INIT

AM_MAINTAINER_MODE([enable])

# Checks for programs.
AC_PROG_CC
AC_PROG_INSTALL
AM_PROG_CC_C_O

# Checks for optional programs.
PROG_TRY_DOXYGEN

AM_CONDITIONAL([HAVE_DOXYGEN], [test -n "$DOXYGEN"])
AS_IF([test -n "$DOXYGEN"], [AC_CONFIG_FILES([apidoc/doxyfile])])

AC_LANG([C])

AC_PROG_CC_C99
if test "$x{ac_cv_prog_cc_c99}" = xno
then
AC_MSG_FAILURE([
--------------------------------------------
A C99 compiler is required to build the
program.
--------------------------------------------
])
fi

gl_EARLY
gl_INIT