Re: [PATCH] Rewrite gdb_mpz::operator==

[Simon Marchi <simark@simark.ca>]

> diff --git a/gdb/gmp-utils.h b/gdb/gmp-utils.h
> index d05c11ecbe4..1bbdd9564fa 100644
> --- a/gdb/gmp-utils.h
> +++ b/gdb/gmp-utils.h
> @@ -323,31 +323,26 @@ struct gdb_mpz
>      return mpz_cmp_si (m_val, other) < 0;
>    }
>  
> -  bool operator== (int other) const
> -  {
> -    return mpz_cmp_si (m_val, other) == 0;
> -  }
> -
> -  bool operator== (long other) const
> -  {
> -    return mpz_cmp_si (m_val, other) == 0;
> -  }
> -
> -  bool operator== (unsigned long other) const
> -  {
> -    return mpz_cmp_ui (m_val, other) == 0;
> -  }
> -
> +  /* We want an operator== that can handle all integer types.  For
> +     types that are 'long' or narrower, we can use a GMP function and
> +     avoid boxing the RHS.  But, because overloading based on integer
> +     type is a pain in C++, we accept all such types here and check
> +     the size in the body.  */
>    template<typename T,
> -	   typename = gdb::Requires<
> -	     gdb::And<std::is_integral<T>,
> -		      std::integral_constant<bool,
> -					     (sizeof (T) > sizeof (long))>>
> -	     >
> -	   >
> -  bool operator== (T src)
> -  {
> -    return *this == gdb_mpz (src);
> +	   typename = gdb::Requires<std::is_integral<T>>>
The template expression would fit on a single line, if you'd prefer to
write it that way.

Otherwise, LGTM.  I think it's now relatively clear what the code tries
to achieve.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

Simon