[SR-2092] Crash When Evaluating Generic Method

[swift-ci]

Previous ID	SR-2092
Radar	None
Original Reporter	BMc68 (JIRA User)
Type	Bug

Environment

El Capitan 10.11.4 (15E65)
XCode Version 7.3 (7D175)

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, CompilerCrash, IRGen
Assignee	@slavapestov
Priority	Medium

md5: 059bcc1857690eab8b5bde09f5f91bda

Issue Description:

I was writing some Swift extensions on Typhoon to genericise getting items out of a Typhoon Factory, and the compiler crashed while attempting to compile the following code.

Code

import Foundation
import Typhoon

extension Factory {

    func getComponent<T: Any>(_: T.Type) -> T {
        if let type = T.self as? AnyClass,
            let component = self.getComponentForClass(type) as? T {
            return component
        } else if let type: Protocol = (T.self as! Protocol),
            let componenet = self.getComponentForProtocol(type) as? T {
            return componenet
        }
        fatalError()
    }
}

Stack Trace

0  swift                    0x0000000103c554eb llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 43
1  swift                    0x0000000103c547d6 llvm::sys::RunSignalHandlers() + 70
2  swift                    0x0000000103c55b4f SignalHandler(int) + 287
3  libsystem_platform.dylib 0x00007fff8ec8452a _sigtramp + 26
4  libsystem_platform.dylib 0x00007fa4cbc73d70 _sigtramp + 1023342688
5  swift                    0x0000000101a71476 swift::irgen::IRGenFunction::emitObjCRetainCall(llvm::Value*) + 70
6  swift                    0x0000000101ae7dbd swift::SILVisitor<(anonymous namespace)::IRGenSILFunction, void>::visit(swift::ValueBase*) + 18685
7  swift                    0x0000000101adfc4b swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 9787
8  swift                    0x0000000101a3afd8 swift::irgen::IRGenModuleDispatcher::emitGlobalTopLevel() + 600
9  swift                    0x0000000101ac6a5e performIRGeneration(swift::IRGenOptions&, swift::ModuleDecl*, swift::SILModule*, llvm::StringRef, llvm::LLVMContext&, swift::SourceFile*, unsigned int) + 1278
10 swift                    0x0000000101ac6f06 swift::performIRGeneration(swift::IRGenOptions&, swift::SourceFile&, swift::SILModule*, llvm::StringRef, llvm::LLVMContext&, unsigned int) + 70
11 swift                    0x00000001019aaa1c performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&) + 15004
12 swift                    0x00000001019a641d frontend_main(llvm::ArrayRef<char const*>, char const*, void*) + 2781
13 swift                    0x00000001019a1e3c main + 1932
14 libdyld.dylib            0x00007fff999d75ad start + 1

[REDACTED]

1.  While emitting IR SIL function @_TFE22*[REDACTED]*CSo7Factory12getComponenturfMxx for 'getComponent' at *[REDACTED]*/Factory+Swift.swift:14:5

[belkadan]

Most recent commit at https://github.com/appsquickly/Typhoon/tree/be16de74ea7bd80d8ffdcbcf503191b86ffbec7e.

[belkadan]

Your code has as! rather than as?, which makes me think it's incorrect anyway, but that doesn't mean the compiler should crash.