tests/mpq/t-get_d.c failure on m68k-linux

[Aldy Hernandez]

Mikael, can you check this on your setup?  I only have the preprocessed 
.i file from the original GCC pr, so I don't have any definitions for 
RANDS, MAXEXP, or even gmp_randstate_ptr.

Thanks.
Aldy

On 02/19/13 14:25, Niels Möller wrote:

> nisse at lysator.liu.se (Niels Möller) writes:
>
>> On the other hand, maybe the test ought to be rewritten. Using mpz_get_d
>> seems unnecessary.
>
> Below is a rewritten check_random (in tests/mpq/t-get_d.c), with fewer
> floating point operations. Works for me (but fails if I increase the
> size of A to 54 bits). Can you check if it solves the problem?
>
> Regards,
> /Niels
>
> void
> check_random (int argc, char **argv)
> {
>    gmp_randstate_ptr rands = RANDS;
>
>    double d;
>    mpq_t q;
>    mpz_t a, t;
>    int exp;
>
>    int test, reps = 100000;
>    int i;
>
>    if (argc == 2)
>       reps = 100 * atoi (argv[1]);
>
>    mpq_init (q);
>    mpz_init (a);
>    mpz_init (t);
>
>    for (test = 0; test < reps; test++)
>      {
>        mpz_rrandomb (a, rands, 53);
>        mpz_urandomb (t, rands, 32);
>        exp = mpz_get_ui (t) % (2*MAXEXP) - MAXEXP;
>
>        d = my_ldexp (mpz_get_d (a), exp);
>        mpq_set_d (q, d);
>        /* Check that n/d = a * 2^exp, or
> 	 d*a 2^{exp} = n */
>        mpz_mul (t, a, mpq_denref (q));
>        if (exp > 0)
> 	mpz_mul_2exp (t, t, exp);
>        else
> 	{
> 	  if (!mpz_divisible_2exp_p (t, -exp))
> 	    goto fail;
> 	  mpz_div_2exp (t, t, -exp);
> 	}
>        if (mpz_cmp (t, mpq_numref (q)) != 0)
> 	{
> 	fail:
> 	  printf ("ERROR (check_random test %d): bad mpq_set_d results\n", test);
> 	  printf ("%.16g\n", d);
> 	  gmp_printf ("%Qd\n", q);
> 	  abort ();
> 	}
>      }
>    mpq_clear (q);
>    mpz_clear (t);
>    mpz_clear (a);
> }
>