[SR-10524] Crash during build (Abort trap: 6)

[swift-ci]

Previous ID	SR-10524
Radar	None
Original Reporter	hhas01 (JIRA User)
Type	Bug

Attachment: Download

Environment

macOS 10.14.4, Xcode 10.2.1

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, CompilerCrash, Serialization
Assignee	None
Priority	Medium

md5: 55010c35ea8e7e93b7f0e809d4525801

Issue Description:

From the log:

<unknown>:0: error: fatal error encountered while reading from module 'sylvia_lang'; please file a bug report with your project and the crash log

• • • DESERIALIZATION FAILURE (please include this section in any bug report) ***
      result not found
      Cross-reference to module 'sylvia_lang'
      ... Nothing
      ... toArray
      ... with type <τ_0_0, τ_0_1 where τ_0_0 : Value, τ_0_0 : BridgingProtocol, τ_0_0 : CoercionProtocol, τ_0_1 : AsArray<τ_0_0>> (Nothing) -> (Scope, τ_0_1) throws -> Array<τ_0_0.SwiftType>

Stack dump: [...]

1. While deserializing SIL vtable for 'Nothing' (in module 'sylvia_lang')
2. While deserializing decl #9 (XREF) in 'sylvia_lang'
3. Cross-reference to module 'sylvia_lang'
... Value
... toArray
... with type <τ_0_0, τ_0_1 where τ_0_0 : Value, τ_0_0 : BridgingProtocol, τ_0_0 : CoercionProtocol, τ_0_1 : AsArray<τ_0_0>> (Value) -> (Scope, τ_0_1) throws -> Array<τ_0_0.SwiftType>
4. While loading members for 'Value' (in module 'sylvia_lang')
5. While deserializing 'toArray' (FuncDecl #14) in 'sylvia_lang'
...

[belkadan]

The function in question looks like this

func toArray<E, T: AsArray<E>>(env: Scope, coercion: T) throws -> T.SwiftType

and I don't think Swift supports that AsArray<E> as a constraint yet. However, since you don't have any subclasses of AsArray, you can simplify this to

func toArray<E>(env: Scope, coercion: AsArray<E>) throws -> AsArray<E>.SwiftType