Re: [Tinycc-devel] match formats and arguments exactly

[Vincent Lefevre]

On 2019-06-22 01:07:17 +0200, Michael Matz wrote:
> On Fri, 21 Jun 2019, Pascal Cuoq wrote:
> > If no-one objects, I will push in a few days the following patch,
> 
> I don't object, but have a request: can you explore if changing the type of
> the respective variable, instead of adding casts, is equivalent? Especially
> the changes in parse_escape_string look as if that's possible.
> (I consider such type change only better than casts, if the former doesn't
> cause further casts elsewhere, of course).

Changing signed integers to unsigned just to avoid casts for
printf-like functions is a bad idea. The reason is that in
some expressions, using unsigned types can silently modify
the value of a signed type when implicitly converted to
unsigned. This is very ugly. FYI, we had bugs like that in
GNU MPFR, and that's why we changed the precision type to
a signed integer type, even though its value is always
positive.

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Vincent Lefèvre <address@hidden> - Web: <https://www.vinc17.net/>
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