srcm4/gnulib-common.m4 - nest-hello/libiconv - Git at Google

 # gnulib-common.m4 serial 29
 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.

 # gl_COMMON
 # is expanded unconditionally through gnulib-tool magic.
 AC_DEFUN([gl_COMMON], [
   dnl Use AC_REQUIRE here, so that the code is expanded once only.
   AC_REQUIRE([gl_00GNULIB])
   AC_REQUIRE([gl_COMMON_BODY])
 ])
 AC_DEFUN([gl_COMMON_BODY], [
   AH_VERBATIM([_Noreturn],
 [/* The _Noreturn keyword of draft C1X.  */
 #ifndef _Noreturn
 # if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
       || 0x5110 <= __SUNPRO_C)
 #  define _Noreturn __attribute__ ((__noreturn__))
 # elif 1200 <= _MSC_VER
 #  define _Noreturn __declspec (noreturn)
 # else
 #  define _Noreturn
 # endif
 #endif
 ])
   AH_VERBATIM([isoc99_inline],
 [/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
    the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
    earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
    __APPLE__ && __MACH__ test for MacOS X.
    __APPLE_CC__ tests for the Apple compiler and its version.
    __STDC_VERSION__ tests for the C99 mode.  */
 #if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
 # define __GNUC_STDC_INLINE__ 1
 #endif])
   AH_VERBATIM([unused_parameter],
 [/* Define as a marker that can be attached to declarations that might not
     be used.  This helps to reduce warnings, such as from
     GCC -Wunused-parameter.  */
 #if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
 # define _GL_UNUSED __attribute__ ((__unused__))
 #else
 # define _GL_UNUSED
 #endif
 /* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
    is a misnomer outside of parameter lists.  */
 #define _UNUSED_PARAMETER_ _GL_UNUSED

 /* The __pure__ attribute was added in gcc 2.96.  */
 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
 # define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
 #else
 # define _GL_ATTRIBUTE_PURE /* empty */
 #endif

 /* The __const__ attribute was added in gcc 2.95.  */
 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
 # define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
 #else
 # define _GL_ATTRIBUTE_CONST /* empty */
 #endif
 ])
   dnl Preparation for running test programs:
   dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
   dnl to /dev/tty, so they can be redirected to log files.  Such diagnostics
   dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
   LIBC_FATAL_STDERR_=1
   export LIBC_FATAL_STDERR_
 ])

 # gl_MODULE_INDICATOR_CONDITION
 # expands to a C preprocessor expression that evaluates to 1 or 0, depending
 # whether a gnulib module that has been requested shall be considered present
 # or not.
 m4_define([gl_MODULE_INDICATOR_CONDITION], [1])

 # gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
 # sets the shell variable that indicates the presence of the given module to
 # a C preprocessor expression that will evaluate to 1.
 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
 [
   gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
     [GNULIB_[]m4_translit([[$1]],
                           [abcdefghijklmnopqrstuvwxyz./-],
                           [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
     [gl_MODULE_INDICATOR_CONDITION])
 ])

 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
 # modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
 # The shell variable's value is a C preprocessor expression that evaluates
 # to 0 or 1.
 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
 [
   m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
     [
      dnl Simplify the expression VALUE || 1 to 1.
      $1=1
     ],
     [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
                                              [gl_MODULE_INDICATOR_CONDITION])])
 ])

 # gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
 # modifies the shell variable to include the given condition.  The shell
 # variable's value is a C preprocessor expression that evaluates to 0 or 1.
 AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
 [
   dnl Simplify the expression 1 || CONDITION to 1.
   if test "$[]$1" != 1; then
     dnl Simplify the expression 0 || CONDITION to CONDITION.
     if test "$[]$1" = 0; then
       $1=$2
     else
       $1="($[]$1 || $2)"
     fi
   fi
 ])

 # gl_MODULE_INDICATOR([modulename])
 # defines a C macro indicating the presence of the given module
 # in a location where it can be used.
 #                                             |  Value  |   Value   |
 #                                             | in lib/ | in tests/ |
 # --------------------------------------------+---------+-----------+
 # Module present among main modules:          |    1    |     1     |
 # --------------------------------------------+---------+-----------+
 # Module present among tests-related modules: |    0    |     1     |
 # --------------------------------------------+---------+-----------+
 # Module not present at all:                  |    0    |     0     |
 # --------------------------------------------+---------+-----------+
 AC_DEFUN([gl_MODULE_INDICATOR],
 [
   AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
       [abcdefghijklmnopqrstuvwxyz./-],
       [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
     [gl_MODULE_INDICATOR_CONDITION],
     [Define to a C preprocessor expression that evaluates to 1 or 0,
      depending whether the gnulib module $1 shall be considered present.])
 ])

 # gl_MODULE_INDICATOR_FOR_TESTS([modulename])
 # defines a C macro indicating the presence of the given module
 # in lib or tests. This is useful to determine whether the module
 # should be tested.
 #                                             |  Value  |   Value   |
 #                                             | in lib/ | in tests/ |
 # --------------------------------------------+---------+-----------+
 # Module present among main modules:          |    1    |     1     |
 # --------------------------------------------+---------+-----------+
 # Module present among tests-related modules: |    1    |     1     |
 # --------------------------------------------+---------+-----------+
 # Module not present at all:                  |    0    |     0     |
 # --------------------------------------------+---------+-----------+
 AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
 [
   AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
       [abcdefghijklmnopqrstuvwxyz./-],
       [ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
     [Define to 1 when the gnulib module $1 should be tested.])
 ])

 # gl_ASSERT_NO_GNULIB_POSIXCHECK
 # asserts that there will never be a need to #define GNULIB_POSIXCHECK.
 # and thereby enables an optimization of configure and config.h.
 # Used by Emacs.
 AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
 [
   dnl Override gl_WARN_ON_USE_PREPARE.
   dnl But hide this definition from 'aclocal'.
   AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
 ])

 # gl_ASSERT_NO_GNULIB_TESTS
 # asserts that there will be no gnulib tests in the scope of the configure.ac
 # and thereby enables an optimization of config.h.
 # Used by Emacs.
 AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
 [
   dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
   AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
 ])

 # Test whether <features.h> exists.
 # Set HAVE_FEATURES_H.
 AC_DEFUN([gl_FEATURES_H],
 [
   AC_CHECK_HEADERS_ONCE([features.h])
   if test $ac_cv_header_features_h = yes; then
     HAVE_FEATURES_H=1
   else
     HAVE_FEATURES_H=0
   fi
   AC_SUBST([HAVE_FEATURES_H])
 ])

 # m4_foreach_w
 # is a backport of autoconf-2.59c's m4_foreach_w.
 # Remove this macro when we can assume autoconf >= 2.60.
 m4_ifndef([m4_foreach_w],
   [m4_define([m4_foreach_w],
     [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])

 # AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
 # ----------------------------------------------------
 # Backport of autoconf-2.63b's macro.
 # Remove this macro when we can assume autoconf >= 2.64.
 m4_ifndef([AS_VAR_IF],
 [m4_define([AS_VAR_IF],
 [AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])

 # gl_PROG_AR_RANLIB
 # Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
 AC_DEFUN([gl_PROG_AR_RANLIB],
 [
   dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
   dnl as "cc", and GCC as "gcc". They have different object file formats and
   dnl library formats. In particular, the GNU binutils programs ar, ranlib
   dnl produce libraries that work only with gcc, not with cc.
   AC_REQUIRE([AC_PROG_CC])
   AC_EGREP_CPP([Amsterdam],
     [
 #ifdef __ACK__
 Amsterdam
 #endif
     ],
     [AR='cc -c.a'
      ARFLAGS='-o'
      RANLIB=':'
     ],
     [dnl Use the Automake-documented default values for AR and ARFLAGS.
      AR='ar'
      ARFLAGS='cru'
      dnl Use the ranlib program if it is available.
      AC_PROG_RANLIB
     ])
   AC_SUBST([AR])
   AC_SUBST([ARFLAGS])
 ])

 # AC_PROG_MKDIR_P
 # is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
 # for interoperability with automake-1.9.6 from autoconf-2.62.
 # Remove this macro when we can assume autoconf >= 2.62 or
 # autoconf >= 2.60 && automake >= 1.10.
 m4_ifdef([AC_PROG_MKDIR_P], [
   dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
   m4_define([AC_PROG_MKDIR_P],
     m4_defn([AC_PROG_MKDIR_P])[
     AC_SUBST([MKDIR_P])])], [
   dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
   AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
     [AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
      MKDIR_P='$(mkdir_p)'
      AC_SUBST([MKDIR_P])])])

 # AC_C_RESTRICT
 # This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
 # so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
 # works.
 # This definition can be removed once autoconf >= 2.62 can be assumed.
 m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],[
 AC_DEFUN([AC_C_RESTRICT],
 [AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
   [ac_cv_c_restrict=no
    # The order here caters to the fact that C++ does not require restrict.
    for ac_kw in __restrict __restrict__ _Restrict restrict; do
      AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
       [[typedef int * int_ptr;
         int foo (int_ptr $ac_kw ip) {
         return ip[0];
        }]],
       [[int s[1];
         int * $ac_kw t = s;
         t[0] = 0;
         return foo(t)]])],
       [ac_cv_c_restrict=$ac_kw])
      test "$ac_cv_c_restrict" != no && break
    done
   ])
  AH_VERBATIM([restrict],
 [/* Define to the equivalent of the C99 'restrict' keyword, or to
    nothing if this is not supported.  Do not define if restrict is
    supported directly.  */
 #undef restrict
 /* Work around a bug in Sun C++: it does not support _Restrict, even
    though the corresponding Sun C compiler does, which causes
    "#define restrict _Restrict" in the previous line.  Perhaps some future
    version of Sun C++ will work with _Restrict; if so, it'll probably
    define __RESTRICT, just as Sun C does.  */
 #if defined __SUNPRO_CC && !defined __RESTRICT
 # define _Restrict
 #endif])
  case $ac_cv_c_restrict in
    restrict) ;;
    no) AC_DEFINE([restrict], []) ;;
    *)  AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
  esac
 ])
 ])

 # gl_BIGENDIAN
 # is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
 # Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
 # macros invoke AC_C_BIGENDIAN with arguments.
 AC_DEFUN([gl_BIGENDIAN],
 [
   AC_C_BIGENDIAN
 ])

 # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
 # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
 # output a spurious "(cached)" mark in the midst of other configure output.
 # This macro should be used instead of AC_CACHE_VAL when it is not surrounded
 # by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
 AC_DEFUN([gl_CACHE_VAL_SILENT],
 [
   saved_as_echo_n="$as_echo_n"
   as_echo_n=':'
   AC_CACHE_VAL([$1], [$2])
   as_echo_n="$saved_as_echo_n"
 ])
	# gnulib-common.m4 serial 29
	dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
	dnl This file is free software; the Free Software Foundation
	dnl gives unlimited permission to copy and/or distribute it,
	dnl with or without modifications, as long as this notice is preserved.

	# gl_COMMON
	# is expanded unconditionally through gnulib-tool magic.
	AC_DEFUN([gl_COMMON], [
	dnl Use AC_REQUIRE here, so that the code is expanded once only.
	AC_REQUIRE([gl_00GNULIB])
	AC_REQUIRE([gl_COMMON_BODY])
	])
	AC_DEFUN([gl_COMMON_BODY], [
	AH_VERBATIM([_Noreturn],
	[/* The _Noreturn keyword of draft C1X. */
	#ifndef _Noreturn
	# if (3 <= __GNUC__ \|\| (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
	\|\| 0x5110 <= __SUNPRO_C)
	# define _Noreturn __attribute__ ((__noreturn__))
	# elif 1200 <= _MSC_VER
	# define _Noreturn __declspec (noreturn)
	# else
	# define _Noreturn
	# endif
	#endif
	])
	AH_VERBATIM([isoc99_inline],
	[/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
	the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
	earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
	__APPLE__ && __MACH__ test for MacOS X.
	__APPLE_CC__ tests for the Apple compiler and its version.
	__STDC_VERSION__ tests for the C99 mode. */
	#if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
	# define __GNUC_STDC_INLINE__ 1
	#endif])
	AH_VERBATIM([unused_parameter],
	[/* Define as a marker that can be attached to declarations that might not
	be used. This helps to reduce warnings, such as from
	GCC -Wunused-parameter. */
	#if __GNUC__ >= 3 \|\| (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
	# define _GL_UNUSED __attribute__ ((__unused__))
	#else
	# define _GL_UNUSED
	#endif
	/* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
	is a misnomer outside of parameter lists. */
	#define _UNUSED_PARAMETER_ _GL_UNUSED

	/* The __pure__ attribute was added in gcc 2.96. */
	#if __GNUC__ > 2 \|\| (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
	# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
	#else
	# define _GL_ATTRIBUTE_PURE /* empty */
	#endif

	/* The __const__ attribute was added in gcc 2.95. */
	#if __GNUC__ > 2 \|\| (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
	# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
	#else
	# define _GL_ATTRIBUTE_CONST /* empty */
	#endif
	])
	dnl Preparation for running test programs:
	dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
	dnl to /dev/tty, so they can be redirected to log files. Such diagnostics
	dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
	LIBC_FATAL_STDERR_=1
	export LIBC_FATAL_STDERR_
	])

	# gl_MODULE_INDICATOR_CONDITION
	# expands to a C preprocessor expression that evaluates to 1 or 0, depending
	# whether a gnulib module that has been requested shall be considered present
	# or not.
	m4_define([gl_MODULE_INDICATOR_CONDITION], [1])

	# gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
	# sets the shell variable that indicates the presence of the given module to
	# a C preprocessor expression that will evaluate to 1.
	AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
	[
	gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
	[GNULIB_[]m4_translit([[$1]],
	[abcdefghijklmnopqrstuvwxyz./-],
	[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
	[gl_MODULE_INDICATOR_CONDITION])
	])

	# gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
	# modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
	# The shell variable's value is a C preprocessor expression that evaluates
	# to 0 or 1.
	AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
	[
	m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
	[
	dnl Simplify the expression VALUE \|\| 1 to 1.
	$1=1
	],
	[gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
	[gl_MODULE_INDICATOR_CONDITION])])
	])

	# gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
	# modifies the shell variable to include the given condition. The shell
	# variable's value is a C preprocessor expression that evaluates to 0 or 1.
	AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
	[
	dnl Simplify the expression 1 \|\| CONDITION to 1.
	if test "$[]$1" != 1; then
	dnl Simplify the expression 0 \|\| CONDITION to CONDITION.
	if test "$[]$1" = 0; then
	$1=$2
	else
	$1="($[]$1 \|\| $2)"
	fi
	fi
	])

	# gl_MODULE_INDICATOR([modulename])
	# defines a C macro indicating the presence of the given module
	# in a location where it can be used.
	# \| Value \| Value \|
	# \| in lib/ \| in tests/ \|
	# --------------------------------------------+---------+-----------+
	# Module present among main modules: \| 1 \| 1 \|
	# --------------------------------------------+---------+-----------+
	# Module present among tests-related modules: \| 0 \| 1 \|
	# --------------------------------------------+---------+-----------+
	# Module not present at all: \| 0 \| 0 \|
	# --------------------------------------------+---------+-----------+
	AC_DEFUN([gl_MODULE_INDICATOR],
	[
	AC_DEFINE_UNQUOTED([GNULIB_]m4_translit([[$1]],
	[abcdefghijklmnopqrstuvwxyz./-],
	[ABCDEFGHIJKLMNOPQRSTUVWXYZ___]),
	[gl_MODULE_INDICATOR_CONDITION],
	[Define to a C preprocessor expression that evaluates to 1 or 0,
	depending whether the gnulib module $1 shall be considered present.])
	])

	# gl_MODULE_INDICATOR_FOR_TESTS([modulename])
	# defines a C macro indicating the presence of the given module
	# in lib or tests. This is useful to determine whether the module
	# should be tested.
	# \| Value \| Value \|
	# \| in lib/ \| in tests/ \|
	# --------------------------------------------+---------+-----------+
	# Module present among main modules: \| 1 \| 1 \|
	# --------------------------------------------+---------+-----------+
	# Module present among tests-related modules: \| 1 \| 1 \|
	# --------------------------------------------+---------+-----------+
	# Module not present at all: \| 0 \| 0 \|
	# --------------------------------------------+---------+-----------+
	AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS],
	[
	AC_DEFINE([GNULIB_TEST_]m4_translit([[$1]],
	[abcdefghijklmnopqrstuvwxyz./-],
	[ABCDEFGHIJKLMNOPQRSTUVWXYZ___]), [1],
	[Define to 1 when the gnulib module $1 should be tested.])
	])

	# gl_ASSERT_NO_GNULIB_POSIXCHECK
	# asserts that there will never be a need to #define GNULIB_POSIXCHECK.
	# and thereby enables an optimization of configure and config.h.
	# Used by Emacs.
	AC_DEFUN([gl_ASSERT_NO_GNULIB_POSIXCHECK],
	[
	dnl Override gl_WARN_ON_USE_PREPARE.
	dnl But hide this definition from 'aclocal'.
	AC_DEFUN([gl_W][ARN_ON_USE_PREPARE], [])
	])

	# gl_ASSERT_NO_GNULIB_TESTS
	# asserts that there will be no gnulib tests in the scope of the configure.ac
	# and thereby enables an optimization of config.h.
	# Used by Emacs.
	AC_DEFUN([gl_ASSERT_NO_GNULIB_TESTS],
	[
	dnl Override gl_MODULE_INDICATOR_FOR_TESTS.
	AC_DEFUN([gl_MODULE_INDICATOR_FOR_TESTS], [])
	])

	# Test whether <features.h> exists.
	# Set HAVE_FEATURES_H.
	AC_DEFUN([gl_FEATURES_H],
	[
	AC_CHECK_HEADERS_ONCE([features.h])
	if test $ac_cv_header_features_h = yes; then
	HAVE_FEATURES_H=1
	else
	HAVE_FEATURES_H=0
	fi
	AC_SUBST([HAVE_FEATURES_H])
	])

	# m4_foreach_w
	# is a backport of autoconf-2.59c's m4_foreach_w.
	# Remove this macro when we can assume autoconf >= 2.60.
	m4_ifndef([m4_foreach_w],
	[m4_define([m4_foreach_w],
	[m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])

	# AS_VAR_IF(VAR, VALUE, [IF-MATCH], [IF-NOT-MATCH])
	# ----------------------------------------------------
	# Backport of autoconf-2.63b's macro.
	# Remove this macro when we can assume autoconf >= 2.64.
	m4_ifndef([AS_VAR_IF],
	[m4_define([AS_VAR_IF],
	[AS_IF([test x"AS_VAR_GET([$1])" = x""$2], [$3], [$4])])])

	# gl_PROG_AR_RANLIB
	# Determines the values for AR, ARFLAGS, RANLIB that fit with the compiler.
	AC_DEFUN([gl_PROG_AR_RANLIB],
	[
	dnl Minix 3 comes with two toolchains: The Amsterdam Compiler Kit compiler
	dnl as "cc", and GCC as "gcc". They have different object file formats and
	dnl library formats. In particular, the GNU binutils programs ar, ranlib
	dnl produce libraries that work only with gcc, not with cc.
	AC_REQUIRE([AC_PROG_CC])
	AC_EGREP_CPP([Amsterdam],
	[
	#ifdef __ACK__
	Amsterdam
	#endif
	],
	[AR='cc -c.a'
	ARFLAGS='-o'
	RANLIB=':'
	],
	[dnl Use the Automake-documented default values for AR and ARFLAGS.
	AR='ar'
	ARFLAGS='cru'
	dnl Use the ranlib program if it is available.
	AC_PROG_RANLIB
	])
	AC_SUBST([AR])
	AC_SUBST([ARFLAGS])
	])

	# AC_PROG_MKDIR_P
	# is a backport of autoconf-2.60's AC_PROG_MKDIR_P, with a fix
	# for interoperability with automake-1.9.6 from autoconf-2.62.
	# Remove this macro when we can assume autoconf >= 2.62 or
	# autoconf >= 2.60 && automake >= 1.10.
	m4_ifdef([AC_PROG_MKDIR_P], [
	dnl For automake-1.9.6 && autoconf < 2.62: Ensure MKDIR_P is AC_SUBSTed.
	m4_define([AC_PROG_MKDIR_P],
	m4_defn([AC_PROG_MKDIR_P])[
	AC_SUBST([MKDIR_P])])], [
	dnl For autoconf < 2.60: Backport of AC_PROG_MKDIR_P.
	AC_DEFUN_ONCE([AC_PROG_MKDIR_P],
	[AC_REQUIRE([AM_PROG_MKDIR_P])dnl defined by automake
	MKDIR_P='$(mkdir_p)'
	AC_SUBST([MKDIR_P])])])

	# AC_C_RESTRICT
	# This definition overrides the AC_C_RESTRICT macro from autoconf 2.60..2.61,
	# so that mixed use of GNU C and GNU C++ and mixed use of Sun C and Sun C++
	# works.
	# This definition can be removed once autoconf >= 2.62 can be assumed.
	m4_if(m4_version_compare(m4_defn([m4_PACKAGE_VERSION]),[2.62]),[-1],[
	AC_DEFUN([AC_C_RESTRICT],
	[AC_CACHE_CHECK([for C/C++ restrict keyword], [ac_cv_c_restrict],
	[ac_cv_c_restrict=no
	# The order here caters to the fact that C++ does not require restrict.
	for ac_kw in __restrict __restrict__ _Restrict restrict; do
	AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
	[[typedef int * int_ptr;
	int foo (int_ptr $ac_kw ip) {
	return ip[0];
	}]],
	[[int s[1];
	int * $ac_kw t = s;
	t[0] = 0;
	return foo(t)]])],
	[ac_cv_c_restrict=$ac_kw])
	test "$ac_cv_c_restrict" != no && break
	done
	])
	AH_VERBATIM([restrict],
	[/* Define to the equivalent of the C99 'restrict' keyword, or to
	nothing if this is not supported. Do not define if restrict is
	supported directly. */
	#undef restrict
	/* Work around a bug in Sun C++: it does not support _Restrict, even
	though the corresponding Sun C compiler does, which causes
	"#define restrict _Restrict" in the previous line. Perhaps some future
	version of Sun C++ will work with _Restrict; if so, it'll probably
	define __RESTRICT, just as Sun C does. */
	#if defined __SUNPRO_CC && !defined __RESTRICT
	# define _Restrict
	#endif])
	case $ac_cv_c_restrict in
	restrict) ;;
	no) AC_DEFINE([restrict], []) ;;
	*) AC_DEFINE_UNQUOTED([restrict], [$ac_cv_c_restrict]) ;;
	esac
	])
	])

	# gl_BIGENDIAN
	# is like AC_C_BIGENDIAN, except that it can be AC_REQUIREd.
	# Note that AC_REQUIRE([AC_C_BIGENDIAN]) does not work reliably because some
	# macros invoke AC_C_BIGENDIAN with arguments.
	AC_DEFUN([gl_BIGENDIAN],
	[
	AC_C_BIGENDIAN
	])

	# gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
	# is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
	# output a spurious "(cached)" mark in the midst of other configure output.
	# This macro should be used instead of AC_CACHE_VAL when it is not surrounded
	# by an AC_MSG_CHECKING/AC_MSG_RESULT pair.
	AC_DEFUN([gl_CACHE_VAL_SILENT],
	[
	saved_as_echo_n="$as_echo_n"
	as_echo_n=':'
	AC_CACHE_VAL([$1], [$2])
	as_echo_n="$saved_as_echo_n"
	])