Re: [PATCH] s390 (7/13): gcc 3.3 adaptions.

From: John Alvord (jalvo@mbay.net)
Date: Mon Feb 24 2003 - 18:52:20 EST


On Mon, 24 Feb 2003 17:39:34 -0500, Jakub Jelinek <jakub@redhat.com>
wrote:

>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)?
>
>Value range propagation pass, then warn?

I know it is stupid/unnecessary etc, but you could do

#if COUNT > INT_MAX
#error you idiot...
#endif

        int i;
        for(i =0; i < (int)COUNT; i++)
        ...

where the #if was placed in whatever header COUNT was defined.

and have safe code with no runtime overhead and looking only mildly
idiotic.

john alvord
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