Re: How to use core.atomic.cas with (function) pointers?

[Nicholas Wilson via Digitalmars-d-learn]

On Tuesday, 22 January 2019 at 14:13:23 UTC, Johan Engelen wrote:
The following code compiles:
```
alias T = shared(int)*;
shared T a;
shared T b;
shared T c;

void foo() {
    import core.atomic: cas;
    cas(&a, b, c);
}
```

The type of T has to be a pointer to a shared int (you get a 
template match error for `cas` if `T = int*`), which is 
annoying but I kind-of understand.
However, change b to null (`cas(&a, null, c);`) and things no 
longer work: "Error: template `core.atomic.cas` cannot deduce 
function from argument types"

I have not succeeded to make things work with function pointers 
(neither with nor without `null` as second argument). What am I 
doing wrong if `alias T = void function();` ?

Thanks,
  Johan

You need to cast stuff (as seems to be the case with everything 
to do with shared, at least until/if Manu's proposal goes 
through):

alias T = void function();
alias S = shared(size_t*);
shared T a;
shared T b;
shared T c;

void foo() {
    import core.atomic: cas;
    cas(cast(S*)&a, cast(S)b, cast(S)c);
}