Re: -Wformat-signedness

On Tue, Nov 10, 2020 at 4:25 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> writes:
> > 1. enums are unsigned by default in gcc, so all those internal error
> > messages "unrecognized blah kind: %d" need to be changed to %u.
>
> Do we have reason to think that that is true in every C compiler?
> My own preference for this would be to leave the messages as-is
> and add explicit "(int)" casts to the arguments. There are some
> fraction of these that are like that already.

From experimentation, it seems that GCC enumerator constants are int,
but enum variables are int or signed int depending on whether any
negative values were defined. Valid values have to be representable
as int anyway regardless of what size and signedness a compiler
chooses to use, so yeah, +1 for casting to int.