[SR-10269] Crash on AnyKeyPath.== infix(_:_:) only on 32-bit devices

[swift-ci]

Previous ID	SR-10269
Radar	None
Original Reporter	Evilutiuoner (JIRA User)
Type	Bug

Environment

• only on iOS 10.x (32 bit devices) but it is 100% reproducible

• only on prod or test-flight Apps, unable to reproduce on dev builds

• Xcode 10.1 b10B61 (Swift 4.2.1)

Additional Detail from JIRA

Votes	0
Component/s	Standard Library
Labels	Bug, 32BitOnly, KeyPaths, RunTimeCrash
Assignee	None
Priority	Medium

md5: ecd1b60c63f24ca82c43cc1192c6169f

Issue Description:

Crashed source code:

public enum NetModelFillingType<Model> {
    case selectedFields(keyPathes: [PartialKeyPath<Model>])
    case notSpecified
}

public protocol StandardNetModelFilling {
    associatedtype Model
    var fillMode: NetModelFillingType<Model> { get }
}

public struct UserNetModel: StandardNetModelFilling {
    public var fillMode = NetModelFillingType<UserNetModel>.notSpecified
    public var firstName: String?
    public var lastName: String?
}

var model = UserNetModel()
model.fillMode = .selectedFields(keyPathes: [\UserNetModel.firstName, \UserNetModel.lastName])


if case .selectedFields(let keyPathes) = model.fillMode {
    for keyPath in keyPathes {
        switch keyPath {
        case \UserNetModel.firstName: break
        case \UserNetModel.lastName: break // crash on accesss !!!!!!!
        default: break
        }
    }
}

Crashed stacktrace:

specialized closure #&#8203;1 in closure #&#8203;1 in static AnyKeyPath.== infix(_:_:) (<compiler-generated>)
partial apply for thunk for @callee_guaranteed (@unowned KeyPathBuffer) -> (@unowned Bool, @error @owned Error) (<compiler-genera
partial apply for thunk for @callee_guaranteed (@unowned KeyPathBuffer) -> (@unowned Bool, @error @owned Error) (<compiler-genera
thunk for @callee_guaranteed (@unowned KeyPathBuffer) -> (@unowned Bool, @error @owned Error)partial apply + 26990833
swift_errorInMain + 498610
UserEntity.updateDataFields(with:in:keyPathes:) (UserEntity.swift:115)

[belkadan]

@mikeash, @jckarter, this is probably different from the alignment thing you were seeing in Swift 5, but does this sound familiar? Was it already fixed?

[belkadan]

Oleg, when you say "only on prod or test-flight Apps, unable to reproduce on dev builds", is that a difference between Debug and Release builds?

[jckarter]

It sounds likely to be related.

[swift-ci]

Comment by Oleg Marchik (JIRA)

@belkadan Release builds (release scheme) distributed by Fabric didn't face this issue. I'm don't understand the difference between the AppStore/TestFlight build and Fabric/Xcode IPA file. Can be it connected with enabled bit code feature?

[belkadan]

I wouldn't expect a difference either.