[SR-8847] DispatchTimeInterval String representation regression Swift 4.2/Ubuntu 18.04

[swift-ci]

Previous ID	SR-8847
Radar	None
Original Reporter	neal@3dsafety.com (JIRA User)
Type	Bug
Status	Resolved
Resolution	Duplicate

Environment

Swift version 4.2

Ubuntu 18.04 64bit

Additional Detail from JIRA

Votes	0
Component/s	libdispatch
Labels	Bug, 4.2Regression
Assignee	neal@3dsafety.com (JIRA)
Priority	Medium

md5: 60b624086d8cf50d44a253821650bf09

relates to:

• SR-8906 Can't print() a DispatchQoS instance on Linux (any longer)

Issue Description:

"\(DispatchTimeInterval.nanoseconds(1))" prints

"nanoseconds(1)" on Swift 4.2/OSX and Swift 4.1/Ubuntu 16.04

but prints

"unknown()" on Swift 4.2/Ubuntu 18.04.

Additionally, on Ubuntu 18.04 the message "SWIFT RUNTIME BUG: unable to find field metadata for type 'Dispatch.DispatchTimeInterval'" is printed to stderr three times.

Please see DispatchTimeIntervalSwift42Testsfor a test which succeeds on Swift 4.2/OSX but fails on Swift 4.2/Ubuntu 18.04.

[belkadan]

cc dgrove-oss (JIRA User), mww (JIRA User)

[jckarter]

This looks like the same issue as https://bugs.swift.org/browse/SR-8906.