[MLton] Re: [MLton-commit] r4510

[Stephen Weeks]

> My worry is more that someone porting to a new platform won't notice
> that they forgot to add the right include that provides the
> constants, because the runtime will compile (but providing none of
> the constants).

To alleviate this, we could eliminate the #ifndef for a few "key"
constants that we really do expect are everywhere.  Then, if a porter
forgets to include the right thing, he will be told.