dnl Fix Autoconf bugs by overriding broken internal Autoconf

dnl macros with backports of fixes from newer releases.

dnl

dnl The override bits of this file should be a no-op for the newest

dnl Autoconf version, which means they can be removed once the complete

dnl tree has moved to a new enough Autoconf version.

dnl

dnl The _GCC_AUTOCONF_VERSION_TEST ensures that exactly the desired

dnl Autoconf version is used.  It should be kept for consistency.

dnl Use ifdef/ifelse over m4_ifdef/m4_ifelse to be clean for 2.13.

ifdef([m4_PACKAGE_VERSION], [

dnl Provide m4_copy_force and m4_rename_force for old Autoconf versions.

m4_ifndef([m4_copy_force],

[m4_define([m4_copy_force],

[m4_ifdef([$2], [m4_undefine([$2])])m4_copy($@)])])

m4_ifndef([m4_rename_force],

[m4_define([m4_rename_force],

[m4_ifdef([$2], [m4_undefine([$2])])m4_rename($@)])])

dnl AC_DEFUN a commonly used macro so this file is picked up.

m4_copy([AC_PREREQ], [_AC_PREREQ])

AC_DEFUN([AC_PREREQ], [frob])

m4_copy_force([_AC_PREREQ], [AC_PREREQ])

dnl Ensure exactly this Autoconf version is used

m4_ifndef([_GCC_AUTOCONF_VERSION],

  [m4_define([_GCC_AUTOCONF_VERSION], [2.69])])

dnl Test for the exact version when AC_INIT is expanded.

dnl This allows to update the tree in steps (for testing)

dnl by putting

dnl   m4_define([_GCC_AUTOCONF_VERSION], [X.Y])

dnl in configure.ac before AC_INIT,

dnl without rewriting this file.

dnl Or for updating the whole tree at once with the definition above.

AC_DEFUN([_GCC_AUTOCONF_VERSION_CHECK],

[m4_if(m4_defn([_GCC_AUTOCONF_VERSION]),

  m4_defn([m4_PACKAGE_VERSION]), [],

  [m4_fatal([Please use exactly Autoconf ]_GCC_AUTOCONF_VERSION[ instead of ]m4_defn([m4_PACKAGE_VERSION])[.])])

])

m4_define([AC_INIT], m4_defn([AC_INIT])[

_GCC_AUTOCONF_VERSION_CHECK

])

dnl Ensure we do not use a buggy M4.

m4_if(m4_index([..wi.d.], [.d.]), [-1],

  [m4_fatal(m4_do([m4 with buggy strstr detected.  Please install

GNU M4 1.4.16 or newer and set the M4 environment variable]))])

dnl Fix 2.64 cross compile detection for AVR and RTEMS

dnl by not trying to compile fopen.

m4_if(m4_defn([m4_PACKAGE_VERSION]), [2.64],

  [m4_foreach([_GCC_LANG], [C, C++, Fortran, Fortran 77],

     [m4_define([_AC_LANG_IO_PROGRAM(]_GCC_LANG[)], m4_defn([AC_LANG_PROGRAM(]_GCC_LANG[)]))])])

m4_version_prereq([2.66],, [

dnl We need AC_CHECK_DECL which works for overloaded C++ functions.

# _AC_CHECK_DECL_BODY

# -------------------

# Shell function body for AC_CHECK_DECL.

m4_define([_AC_CHECK_DECL_BODY],

[  AS_LINENO_PUSH([$[]1])

  [as_decl_name=`echo $][2|sed 's/ *(.*//'`]

  [as_decl_use=`echo $][2|sed -e 's/(/((/' -e 's/)/) 0&/' -e 's/,/) 0& (/g'`]

  AC_CACHE_CHECK([whether $as_decl_name is declared], [$[]3],

  [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([$[]4],

[@%:@ifndef $[]as_decl_name

@%:@ifdef __cplusplus

  (void) $[]as_decl_use;

@%:@else

  (void) $[]as_decl_name;

@%:@endif

@%:@endif

])],

		   [AS_VAR_SET([$[]3], [yes])],

		   [AS_VAR_SET([$[]3], [no])])])

  AS_LINENO_POP

])# _AC_CHECK_DECL_BODY

# _AC_CHECK_DECLS(SYMBOL, ACTION-IF_FOUND, ACTION-IF-NOT-FOUND,

#                 INCLUDES)

# -------------------------------------------------------------

# Helper to AC_CHECK_DECLS, which generates the check for a single

# SYMBOL with INCLUDES, performs the AC_DEFINE, then expands

# ACTION-IF-FOUND or ACTION-IF-NOT-FOUND.

m4_define([_AC_CHECK_DECLS],

[AC_CHECK_DECL([$1], [ac_have_decl=1], [ac_have_decl=0], [$4])]dnl

[AC_DEFINE_UNQUOTED(AS_TR_CPP(m4_bpatsubst(HAVE_DECL_[$1],[ *(.*])),

  [$ac_have_decl],

  [Define to 1 if you have the declaration of `$1',

   and to 0 if you don't.])]dnl

[m4_ifvaln([$2$3], [AS_IF([test $ac_have_decl = 1], [$2], [$3])])])

])

dnl If flex/lex are not found, the top level configure sets LEX to

dnl "/path_to/missing flex".  When AC_PROG_LEX tries to find the flex

dnl output file, it calls $LEX to do so, but the current lightweight

dnl "missing" won't create a file.  This results in an error.

dnl Avoid calling the bulk of AC_PROG_LEX when $LEX is "missing".

AC_DEFUN_ONCE([AC_PROG_LEX],

[AC_CHECK_PROGS(LEX, flex lex, :)

case "$LEX" in

  :|*"missing "*) ;;

  *) _AC_PROG_LEX_YYTEXT_DECL ;;

esac])

])