AC_DEFUN(sr_STRUCT_TM_ISDST,
[AC_REQUIRE([AC_STRUCT_TM])dnl
AC_CACHE_CHECK([for tm_isdst in struct tm], ac_cv_struct_tm_isdst,
[AC_TRY_COMPILE([#include <sys/types.h>
#include <$ac_cv_struct_tm>], [struct tm tm; tm.tm_isdst;],
  ac_cv_struct_tm_isdst=yes, ac_cv_struct_tm_isdst=no)])
if test "$ac_cv_struct_tm_isdst" = yes; then
  AC_DEFINE(HAVE_TM_ISDST)
fi
])