Re: PgStat_HashKey padding issue when passed by reference

> > This looks like a compiler bug, we tested multiple ways to workaround:
>
> Padding bytes aren't guaranteed to be zeroed, unless you take care to zero
> them out with memset or such. That's not a compiler bug.

Perhaps calling this a compiler bug is not appropriate.
However, memset is in fact called when the key is created

```
  /* clear padding */
  memset(&key, 0, sizeof(struct PgStat_HashKey));
```

but the zeroed out padding bytes are not retained when the
key is passed by value. This is why the proposal is to pass the
key by reference.

--
Sami Imseih
Amazon Web Services (AWS)