Swift: Compiler crashes on a function passing a AutoreleasingUnsafeMutablePointer of a stack variable of generic type into a function

Originator:rix.rob
Number:rdar://19091061 Date Originated:27-Nov-2014 03:56 PM
Status:Open Resolved:
Product:Developer Tools Product Version:Xcode 6.1.1 (6A2006)
Classification:Crash/Hang/Data Loss Reproducible:Always
 
Summary:
Segfault on `init` in the code sample below.


Steps to Reproduce:
1. Code:
struct S<T> {
	init(f: AutoreleasingUnsafeMutablePointer<T?> -> ()) {
		var t: T?
		f(&t)
	}
}


Expected Results:
😄


Actual Results:
💥


Regression:
Changing the init to this does not crash:

	init(f: (inout T?) -> ()) {
		var t: T?
		f(&t)
	}

It crashes but without any stack dump if you don’t use a generic type:

struct S {
	init(f: AutoreleasingUnsafeMutablePointer<Int?> -> ()) {
		var t: Int?
		f(&t)
	}
}


Notes:
I kinda wanted to make a Result enum constructor doing something like this with NSError:

https://github.com/LlamaKit/LlamaKit/pull/14

Comments


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