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Re: Request for warnings on implicit bool to int conversions

Russ Allbery <> writes:

> Yeah.  But I suspect it was a mistaken statement.  The subject line from
> the referenced comp.lang.c thread was:

>     c99 and the lack of warnings when int operations are applied to a bool

> which I think is best caught by the conversion *to* bool when the result
> is stored, rather than the conversion *from* bool to perform the
> operation.

I've just briefly reviewed the thread, and it was about both, including
some discussion of warning about any operation that promotes a bool to
some other integer type, on the grounds that a bool would ideally be
treated as a special enumeration that didn't behave like an integer.
(With others pointing out that that isn't the programming language that we
have, as appealing as it might have been if designing C from scratch.)

But I think most of the *practical* problems would be caught by warning
about the implicit integer conversion to bool, if there's a way to wedge
that warning into the language.  (I suspect it might be hard because the
integer conversion may happen under the hood in lots of places that people
don't expect, but I don't know much about the internals.)

Russ Allbery (             <>

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