[cfe-dev] clang-tidy: Inconsistent chain of reasoning using

[Anders Waldenborg via cfe-dev]

Artem Dergachev via cfe-dev writes:
>
> Had a look, thanks! It's one of those nasty pointer cast representation
> bugs:

Hi,

the last few days I've been chasing a false positive in our code base
which I believe is similar to this. I managed to minimize down to:

int hasharray(void **d) {
        void *entries[1];
        entries[0] = d[0];

        char *buf = (char *)entries;
        return buf[1]; // warning: Undefined or garbage value returned to caller
}

clang_analyzer_getExtent of `entries` is 8, whereas for `buf` is it 1.

I find it quite interesting that by changing `entries` to just be a
single pointer rather than an array it works as expected.


Not sure this helps you in any way, but thought it might be good to
share it.

 anders