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Re: Warning for different pointer signedness
On Mon, Dec 20, 2004 at 11:14:58PM +0100, Gabriel Dos Reis wrote:
> Yes, that means they springle cast as approppriate, not that an
> implicit conversion on pointers is performed.
>
> | So
> | int foo (unsigned char *p) { return strcmp (p, "foo"); }
> | will always work correctly. But now the compiler emits an
> | unconditional warning. This seems dubious to me. The code is safe.
>
> The code looks dubious to me, as in real life it would hardly pass
> code-review stage.
Sorry, Gaby, I don't buy this argument, given the C aliasing rules.
C says a pointer to unsigned T and a pointer to signed T can point to
the same object. C specifies the meaning of the foo routine above.
There is no ambiguity with the code. I think that we were right before,
when we warned about this code only when -pedantic was specified.