Re: [PATCH 2/3] build: avoid compile warnings in factor.c on some systems

[Jim Meyering]

Pádraig Brady wrote:
> * src/factor.c (factor_using_pollard_rho2): On some systems
> (like sparc) we need to promote all addmod2() parameters
> to uintmax_t to avoid warnings.
> ---
>  src/factor.c |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/src/factor.c b/src/factor.c
> index 73c59e9..539a686 100644
> --- a/src/factor.c
> +++ b/src/factor.c
> @@ -1532,7 +1532,7 @@ factor_using_pollard_rho2 (uintmax_t n1, uintmax_t n0, 
> unsigned long int a,
>              {
>                x0 = mulredc2 (&r1m, x1, x0, x1, x0, n1, n0, ni);
>                x1 = r1m;
> -              addmod2 (x1, x0, x1, x0, 0, a, n1, n0);
> +              addmod2 (x1, x0, x1, x0, 0, (uintmax_t) a, n1, n0);
>
>                submod2 (t1, t0, z1, z0, x1, x0, n1, n0);
>                P0 = mulredc2 (&r1m, P1, P0, t1, t0, n1, n0, ni);
> @@ -1555,7 +1555,7 @@ factor_using_pollard_rho2 (uintmax_t n1, uintmax_t n0, 
> unsigned long int a,
>              {
>                x0 = mulredc2 (&r1m, x1, x0, x1, x0, n1, n0, ni);
>                x1 = r1m;
> -              addmod2 (x1, x0, x1, x0, 0, a, n1, n0);
> +              addmod2 (x1, x0, x1, x0, 0, (uintmax_t) a, n1, n0);
>              }
>            y1 = x1; y0 = x0;
>          }
> @@ -1565,7 +1565,7 @@ factor_using_pollard_rho2 (uintmax_t n1, uintmax_t n0, 
> unsigned long int a,
>          {
>            y0 = mulredc2 (&r1m, y1, y0, y1, y0, n1, n0, ni);
>            y1 = r1m;
> -          addmod2 (y1, y0, y1, y0, 0, a, n1, n0);
> +          addmod2 (y1, y0, y1, y0, 0, (uintmax_t) a, n1, n0);
>
>            submod2 (t1, t0, z1, z0, y1, y0, n1, n0);
>            g0 = gcd2_odd (&g1, t1, t0, n1, n0);

Thanks.
I confirmed that this addresses the problem.

Did you consider other ways of addressing it,
say without adding that cast?  Imagine that
someone adds another addmod2 use in this code...
They will have to know to widen any argument that may
be narrower than uintmax_t.