Block.swift:14:8: error: no such module '_SwiftDispatchOverlayShims'

Hi!

When build Swift 5.2.2 on linux - there are random periodic errors like this:

Block.swift:14:8: error: no such module '_SwiftDispatchOverlayShims

or

Dispatch.swift:13:19: error: no such module 'Dispatch'

I thought it was because of the parallel build. Then i used options

build-args=-j1
swift-tools-max-parallel-lto-link-jobs=1

it just slowed down the build. Errors keep happening.

How i can solve this problem once and for all?

As I pointed out when you brought this up last month, this is a random flake that likely hasn't been looked into. Unless you reproduce it consistently now, my advice is the same as before.

I can't reproduce this error, it occurs 1 in 3 build. You have such errors in ci too:

I'd appreciate a clue as to which direction to look...