Using a pre-computed array in another function?

[Alasdair McAndrew]

Thanks for that, but I don't think that's the cause of it: I tested a loop
to print some of the A[i] values and they're all there.  It's just that for
some reason, the A[i] values are "invisible" to my mpz_myfun function.

Thanks,
Alasdair

On Sun, Jul 8, 2012 at 6:50 PM, Gabriel Risterucci <cleyfaye at gmail.com>wrote:

> 2012/7/8 Alasdair McAndrew <amca01 at gmail.com>
>
>> Hi there,
>>
>> I have a pre-computed array, which I'd like to use in another function.
>>  This program shows the sort of thing I'm trying to do - I've created an
>> array A in the main program, and I need to use those values in my function
>> "mpz_myfun".  However, this gives me a segmentation fault.
>>
>> Any ideas as to how I can fix this up so it works?  Oh, I'm using gcc
>> version 4.6.1 (Ubuntu/Linaro 4.6.1-9ubuntu3) and gmp 5.0.5.
>>
>> Thanks,
>> Alasdair
>>
>> #include <stdio.h>
>> #include <stdlib.h>
>> #include <gmp.h>
>>
>> mpz_t b,r,j,p,T,n,out;
>> mpz_t *A;
>>
>> void mpz_myfun(mpz_t r,mpz_t m)
>> {
>>   gmp_printf("Zd\n",A[100]);
>>   mpz_t tmp;
>>   mpz_init(tmp);
>>   mpz_and(tmp,m,T);
>>   mpz_set(r,A[mpz_get_ui(tmp)]);
>>   mpz_clear (tmp);
>> }
>>
>> int main(int argc, char *argv[])
>> {
>>    mpz_init_set_ui(b,7);
>>    mpz_init_set_ui(T,65535);
>>    mpz_init_set_ui(p,0x7FFFFFFF);
>>    mpz_init(j);
>>    mpz_t *A = malloc(65536*sizeof(mpz_t));
>>    for (unsigned long i=0; i<65536; i++)
>>      {
>>        mpz_powm_ui(A[i],b,i,p);
>>      }
>>
>>    mpz_init_set_str(n,argv[1],10);
>>    mpz_init(out);
>>
>>    mpz_myfun(out,n);
>>
>>    gmp_printf("%ZD\n",out);
>>
>>    return 0;
>> }
>> _______________________________________________
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>>
>
> You seem to be missing to call mpz_init() on all of your array values.
> Your malloc only allocate space for the mpz_t variables, but you should
> initialize them like any other mpz_t.
>



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