[SR-5887] Data crashes when using subscripts with non-zero lower bounds #4066

swift-ci · 2017-09-15T10:02:22Z

Environment

Latest Xcode GM (9A235)

Additional Detail from JIRA

md5: a40e33dda90e14803763da1dfdb27b81

Issue Description:

When I use the range-based subscript on Data with a non-zero lowerbound, I consistently get a crash.

Example:

 
import Foundation
let data = "hello".data(using: .utf8)! // 5 bytes
data.subdata(in: 1..<3) // this works as expected
data[1..<3] // this crashes

The subscript works fine when the lowerbound is zero.

swift-ci · 2017-09-15T12:21:14Z

Comment by Chris Eidhof (JIRA)

Other methods are broken as well:

data.suffix(from: 1)

swift-ci · 2017-09-15T12:28:58Z

Comment by Chris Eidhof (JIRA)

Ok, the plot thickens. It turns out this only happens in a playground. Probably a playground-quicklookable problem.

swift-ci · 2017-09-15T12:33:04Z

Comment by Chris Eidhof (JIRA)

I'm pretty sure this line is the culprit:

It should almost certainly use startIndex, not 0.

belkadan · 2017-09-15T16:54:22Z

swift-ci transferred this issue from apple/swift-issues Apr 25, 2022

shahmishal transferred this issue from apple/swift May 5, 2022

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