[RFC] Prevent tailcall optimizations of libdl functions

[Florian Weimer]

On 01/25/2017 04:38 PM, Szabolcs Nagy wrote:
> On 25/01/17 15:32, Yuri Gribov wrote:
>> FWIW it sounds like GCC attribute would be the most natural solution
>> (and probably also useful in other contexts). I'll try to cook a patch
>> for GCC if there are no objections.
>
> note that even if dlsym is marked notailcall, with
>
> p = dlsym;
> ...
> return p();
>
> if the type of p does not carry the attributes of
> dlsym then this can be a tailcall.

Yes, but dlsym would still see the address of the function containing 
the dlsym call, which is what we need to determine the relevant object.

Thanks,
Florian