[Distutils] status check on PEP 517

[Donald Stufft]

The only way to avoid it is to not have a circular dependency. 

Sent from my iPhone

> On Jul 29, 2017, at 5:48 PM, Daniel Holth <dholth at gmail.com> wrote:
> 
> I think the proposal is that flit depends on click depends on flit and neither one has a wheel and must be built from sdists. Then you have a circular build problem. So don't do that. I put this in the same category as accidentally conflicting with a stdlib module; it is confusing when it happens but it's also fairly avoidable.