Open Radar

 
Summary:
Algebraic types make Swift 2 sad.


Steps to Reproduce:
1. Compile this _with swiftc_. I repeat, _swiftc_. It does _not_ crash with _swift_, only with _swiftc_:

enum E<T> {
	func map<U>(_ : T -> U) -> E<U> { return .C }
	case C
}
enum Either<T, U> {
	case Left(T)
	case Right(U)
	func either<V>(ifLeft ifLeft: T -> V, ifRight: U -> V) -> V {
		switch self {
		case let .Left(t):
			return ifLeft(t)
		case let .Right(u):
			return ifRight(u)
		}
	}
}
protocol FixpointType {
	typealias Recur

	init(_ : Recur)
	var out: Recur { get }
}
func map<T, U>(f: T -> U)(_ c: E<T>) -> E<U> { return E.map(c)(f) }
func apo<T, Fix: FixpointType where Fix.Recur == E<Fix>>(f: T -> E<Either<Fix, T>>)(_ seed: T) -> Fix {
	let fanin = { Either<Fix, T>.either($0)(ifLeft: {$0}, ifRight: { apo(f)($0) }) }
	return Fix((map(fanin))(f(seed)))
}


Expected Results:
should not crash


Actual Results:
but totally does:
Assertion failed: (ptr->getType()->getPointerElementType() == StorageType), function getAddressForPointer, file /Library/Caches/com.apple.xbs/Sources/swiftlang/swiftlang-700.0.38.1/src/swift/lib/IRGen/GenType.cpp, line 311.
0  swift                    0x000000010d10de0b llvm::sys::PrintStackTrace(__sFILE*) + 43
1  swift                    0x000000010d10e54b SignalHandler(int) + 379
2  libsystem_platform.dylib 0x00007fff88493f1a _sigtramp + 26
3  libsystem_platform.dylib 0x00007f8d24851860 _sigtramp + 2621167968
4  libsystem_c.dylib        0x00007fff86f90b53 abort + 129
5  libsystem_c.dylib        0x00007fff86f58c39 basename + 0
6  swift                    0x000000010b22b7d6 swift::irgen::TypeInfo::getAddressForPointer(llvm::Value*) const + 70
7  swift                    0x000000010b256caa bindParameter((anonymous namespace)::IRGenSILFunction&, swift::SILArgument*, swift::irgen::Explosion&) + 154
8  swift                    0x000000010b252def (anonymous namespace)::IRGenSILFunction::emitSILFunction() + 3279
9  swift                    0x000000010b251d52 swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 498
…
Stack dump:
0.	Program arguments: /Applications/Xcode-7-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift -frontend -c -primary-file recur.swift -target x86_64-apple-darwin14.3.0 -enable-objc-interop -module-name recur -o /var/folders/9y/f7n4rvx901nctm_5d16c1wm40000gn/T/recur-2efa8f.o 
1.	While emitting IR SIL function @_TFF5recur3apou0_Rq0_S_12FixpointTypezqq0_S0_5RecurGOS_1Eq0___FFq_GS1_GOS_6Eitherq0_q___Fq_q0_U_FGS2_Q0_Q__Q0_ for expression at [recur.swift:25:14 - line:25:81] RangeText="{ Either<Fix, T>.either($0)(ifLeft: {$0}, ifRight: { apo(f)($0) }) }"
<unknown>:0: error: unable to execute command: Abort trap: 6
<unknown>:0: error: swift frontend command failed due to signal (use -v to see invocation)


Regression:
This didn’t crash in Swift 1.2.
Haven’t figured out a workaround yet.


Notes:
Maybe if I don’t have any functions at all, maybe then Swift 2 will love me.