Re: [PATCH] Implement warning for wrong use of ||/&&

["Manuel López-Ibáñez" <lopezibanez at gmail dot com>]

On 12/02/07, Dirk Mueller <dmueller@suse.de> wrote:
> +
> +         switch (code)
> +           {
> +           case TRUTH_ANDIF_EXPR:
> +           case TRUTH_ORIF_EXPR:
> +            case TRUTH_AND_EXPR:
> +            case TRUTH_OR_EXPR:
> +             if (INTEGRAL_TYPE_P (TREE_TYPE (arg1))
> +                   && !CONSTANT_CLASS_P (arg1)
> +                   && !expl_eq_arg1
> +                   && TREE_CODE (arg2) == INTEGER_CST
> +                   && !integer_zerop (arg2))
> +               {
> +                 warning (OPT_Walways_true, "logical %<%s%> with non-zero constant "
> +                          "will always evaluate as true",
> +                          ((code == TRUTH_ANDIF_EXPR)
> +                           || (code == TRUTH_AND_EXPR)) ? "&&" : "||");
> +                 expl_eq_arg1 = expl_eq_arg2 = true;
> +               }

Just a nitpick. This will print "&&" or "||" even if the code contains
"and" or "or". I think there is already a bug about this somewhere but
I am not sure whether it is a general defect in GCC or something that
must be fixed case by case.

Cheers,

Manuel.