Rollup of 8 pull requests#74313

Merged

bors merged 25 commits intorust-lang:masterfrom

Manishearth:rollup-b55rn6t

Jul 14, 2020

Commits on Jun 29, 2020

Document the union keyword
poliorcetics
committed

Commits on Jun 30, 2020

Clarify some parts by applying the suggestions from review

poliorcetics
and
joshtriplett
authored

Commits on Jul 4, 2020

Fix caching issue when building tools.
ehuss
committed

Commits on Jul 7, 2020

clean up E0718 explanation
GuillaumeGomez
committed

Commits on Jul 8, 2020

rustdoc: Allow linking from private items to private types
dennis-hamester
committed

Commits on Jul 12, 2020

Update RELEASES.md for 1.45.0

XAMPPRocky
authored and
Mark-Simulacrum
committed

Commits on Jul 14, 2020