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ax_check_define

Synopsis

AC_CHECK_DEFINE([symbol], [ACTION-IF-FOUND], [ACTION-IF-NOT])
AX_CHECK_DEFINE([includes],[symbol], [ACTION-IF-FOUND], [ACTION-IF-NOT])

Description

complements AC_CHECK_FUNC but it does not check for a function but for a define to exist. Consider a usage like AC_CHECK_DEFINE(__STRICT_ANSI__, CFLAGS="$CFLAGS -D_XOPEN_SOURCE=500")

Author

Guido Draheim <guidod@gmx.de>

Last Modified

2005-01-22

M4 Source Code

AC_DEFUN([AC_CHECK_DEFINED],[
AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$1])dnl
AC_CACHE_CHECK([for $1 defined], ac_var,
AC_TRY_COMPILE(,[
  #ifdef $1
  int ok;
  #else
  choke me
  #endif
],AS_VAR_SET(ac_var, yes),AS_VAR_SET(ac_var, no)))
AS_IF([test AS_VAR_GET(ac_var) != "no"], [$2], [$3])dnl
AS_VAR_POPDEF([ac_var])dnl
])

AC_DEFUN([AX_CHECK_DEFINED],[
AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$2])dnl
AC_CACHE_CHECK([for $1 defined], ac_var,
AC_TRY_COMPILE($1,[
  #ifndef $2
  int ok;
  #else
  choke me
  #endif
],AS_VAR_SET(ac_var, yes),AS_VAR_SET(ac_var, no)))
AS_IF([test AS_VAR_GET(ac_var) != "no"], [$3], [$4])dnl
AS_VAR_POPDEF([ac_var])dnl
])

AC_DEFUN([AX_CHECK_FUNC],
[AS_VAR_PUSHDEF([ac_var], [ac_cv_func_$2])dnl
AC_CACHE_CHECK([for $2], ac_var,
dnl AC_LANG_FUNC_LINK_TRY
[AC_LINK_IFELSE([AC_LANG_PROGRAM([$1
                #undef $2
                char $2 ();],[
                char (*f) () = $2;
                return f != $2; ])],
                [AS_VAR_SET(ac_var, yes)],
                [AS_VAR_SET(ac_var, no)])])
AS_IF([test AS_VAR_GET(ac_var) = yes], [$3], [$4])dnl
AS_VAR_POPDEF([ac_var])dnl
])# AC_CHECK_FUNC