Corey Farwell 996f06fe35 Rollup merge of #41061 - arielb1:parent-lock, r=eddyb
cstore: return an immutable borrow from `visible_parent_map`

This prevents an ICE when `visible_parent_map` is called multiple times, for example when an item referenced in an impl signature is imported from an  `extern crate` statement occurs within an impl.

Fixes #41053.

r? @eddyb
2017-04-07 09:20:06 -04:00
..