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    SubjectRe: [PATCH] s390 (7/13): gcc 3.3 adaptions.
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    Jörn Engel <joern@wohnheim.fh-wedel.de> writes:

    |> On Mon, 24 February 2003 23:07:25 +0100, Andreas Schwab wrote:
    |> >
    |> > Jeff Garzik <jgarzik@pobox.com> writes:
    |> >
    |> > |> On Mon, Feb 24, 2003 at 10:35:24PM +0100, Andreas Schwab wrote:
    |> > |> > Linus Torvalds <torvalds@transmeta.com> writes:
    |> > |> >
    |> > |> > |> Does gcc still warn about things like
    |> > |> > |>
    |> > |> > |> #define COUNT (sizeof(array)/sizeof(element))
    |> > |> > |>
    |> > |> > |> int i;
    |> > |> > |> for (i = 0; i < COUNT; i++)
    |> > |> > |> ...
    |> > |> > |>
    |> > |> > |> where COUNT is obviously unsigned (because sizeof is size_t and thus
    |> > |> > |> unsigned)?
    |> > |> > |>
    |> > |> > |> Gcc used to complain about things like that, which is a FUCKING DISASTER.
    |> > |> >
    |> > |> > How can you distinguish that from other occurrences of (int)<(size_t)?
    |> > |>
    |> > |> The bounds are obviously constant and unsigned at compile time.
    |> >
    |> > But that's not the point. It's the runtime value of i that gets converted
    |> > (to unsigned), not the compile time value of COUNT. Thus if i ever gets
    |> > negative you have a problem.
    |>
    |> COUNT is constant and COUNT < INT_MAX. gcc can cast the constant bound
    |> to the variable's type to fix this problem.

    This is not how C works.

    Andreas.

    --
    Andreas Schwab, SuSE Labs, schwab@suse.de
    SuSE Linux AG, Deutschherrnstr. 15-19, D-90429 Nürnberg
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    "And now for something completely different."
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