Audit library for macro usage

Per the C standard:

```
"unless explicitly stated otherwise in the detailed descriptions [...] For the same syntactic reason, it is permitted to take the address of a library function even if it is also defined as a macro"
```

The related footnote states:

> 185) This means that an implementation shall provide an actual function for each library function, even if it also provides a macro for that function.

Should audit library usage to make sure this is followed.