crypto/heimdal/cf/check-declaration.m4

   1 dnl $Id: check-declaration.m4,v 1.3 1999/03/01 13:03:08 joda Exp $
   2 dnl
   3 dnl
   4 dnl Check if we need the declaration of a variable
   5 dnl
   6
   7 dnl AC_HAVE_DECLARATION(includes, variable)
   8 AC_DEFUN(AC_CHECK_DECLARATION, [
   9 AC_MSG_CHECKING([if $2 is properly declared])
  10 AC_CACHE_VAL(ac_cv_var_$2_declaration, [
  11 AC_TRY_COMPILE([$1
  12 extern struct { int foo; } $2;],
  13 [$2.foo = 1;],
  14 eval "ac_cv_var_$2_declaration=no",
  15 eval "ac_cv_var_$2_declaration=yes")
  16 ])
  17
  18 define(foo, [HAVE_]translit($2, [a-z], [A-Z])[_DECLARATION])
  19
  20 AC_MSG_RESULT($ac_cv_var_$2_declaration)
  21 if eval "test \"\$ac_cv_var_$2_declaration\" = yes"; then
  22         AC_DEFINE(foo, 1, [define if your system declares $2])
  23 fi
  24 undefine([foo])
  25 ])