Re: Casting the return value of ...

On 03/28/24 8:09 AM, Kenny McCormack wrote:

 But here's the thing.  Is the casting of the result of dlsym() necessary?
Isn't this the same as "casting the return value of malloc()", where you
don't need to cast it since it auto-magically gets casted by being assigned
to the thing on the left of the assignment? 

No, it isn't even remotely the same. C language allows implicit casts from any object pointer type to `void *` and vice-versa. Which is why casting the result of `malloc` is unnecessary.
C language does not support implicit casts between object pointer types (like `void *`) and function pointer types. Moreover, C language still does not support _explicit_ casts between `void *` and function pointer types either. POSIX guarantees/requirements are not C.

And why do we even need the "clumsy" cast?  Why not just:
                    cosine = dlsym(handle, "cos");

Because this is a constraint violation, aka a "compile error".
--
Best regards,
Andrey