Use correct OpenSSL thread safety macros on OS X (closes #209) Create an Autoconf test to determine if pthread_t is a pointer or scalar type, and use the appropriate CRYPTO_THREADID_set macro based on the result.

table t : {A : int, B : int}
  PRIMARY KEY {{primary_key [#A] [[B = _]]}}

fun main () : transaction page =
    queryI (SELECT * FROM t) (fn _ => return ());
    return <xml/>