[SR-5546] Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!") #48118

weissi · 2017-07-24T18:50:39Z


Previous ID	SR-5546
Radar	rdar://problem/33509989
Original Reporter	@weissi
Type	Bug
Status	Resolved
Resolution	Done

Attachment: Download

Additional Detail from JIRA


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

md5: 50c08792daff0f3df2d6e7f7ed336709

relates to:

SR-6516 error: reference to invalid associated type 'Context' of type 'S'
SR-8813 Using implicit associatedtype in a stored property defined by typealias segfaults the compiler

Issue Description:

The following code

public struct Foo<A, B, C> {}

public protocol P {
    associatedtype PA
    associatedtype PB = Never
    associatedtype PC = Never

    typealias Context = Foo<PA, PB, PC>

    func f1(_ x: Context, _ y: PA)
    func f2(_ x: Context, _ y: PB)
    func f3(_ x: Context, _ y: PC)
    func f4(_ x: Context)
}

public extension P {
    public func f1(_ x: Context, _ y: PA) {
    }
    public func f2(_ x: Context, _ y: PB) {
    }
    public func f3(_ x: Context, _ y: PC) {
    }
    public func f4(_ x: Context) {
    }
}

public struct S: P {
    public typealias PA = String
    public typealias PB = Int

    public func f1(_ x: Context, _ y: PA) {
    }
    public func f2(_ x: Context, _ y: PB) {
    }
}

makes Apple Swift version 4.0-dev (LLVM 2c7b572db2, Clang 54c8e38855, Swift d84e4b4de1) crash with

$ /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2017-07-10-a.xctoolchain/usr/bin/swiftc  test2.swift Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!"), function cast, file /Users/buildnode/jenkins/workspace/oss-swift-package-osx/llvm/include/llvm/Support/Casting.h, line 236.
0  swift                    0x000000010f7cfd08 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 40
1  swift                    0x000000010f7cec66 llvm::sys::RunSignalHandlers() + 86
2  swift                    0x000000010f7d02ce SignalHandler(int) + 366
3  libsystem_platform.dylib 0x00007fff6e8d8f5a _sigtramp + 26
4  libsystem_platform.dylib 0x00007ffee34c69d0 _sigtramp + 1958664848
5  libsystem_c.dylib        0x00007fff6e703cea abort + 127
6  libsystem_c.dylib        0x00007fff6e6cbd40 basename_r + 0
7  swift                    0x000000010d6b2872 (anonymous namespace)::Verifier::verifyChecked(swift::AbstractFunctionDecl*) + 818
8  swift                    0x000000010d6a959a (anonymous namespace)::Verifier::walkToDeclPost(swift::Decl*) + 5482
9  swift                    0x000000010d6b3164 (anonymous namespace)::Traversal::doIt(swift::Decl*) + 388
10 swift                    0x000000010d6b9dcb (anonymous namespace)::Traversal::visitNominalTypeDecl(swift::NominalTypeDecl*) + 443
11 swift                    0x000000010d6b3126 (anonymous namespace)::Traversal::doIt(swift::Decl*) + 326
12 swift                    0x000000010d6b2fcb swift::Decl::walk(swift::ASTWalker&) + 27
13 swift                    0x000000010d74090a swift::SourceFile::walk(swift::ASTWalker&) + 170
14 swift                    0x000000010d6a231b swift::verify(swift::SourceFile&) + 59
15 swift                    0x000000010d622fbd swift::performTypeChecking(swift::SourceFile&, swift::TopLevelContext&, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>, unsigned int, unsigned int, unsigned int, unsigned int) + 2125
16 swift                    0x000000010d17720f swift::CompilerInstance::performSema() + 3535
17 swift                    0x000000010c7792ea performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&, swift::FrontendObserver*, swift::UnifiedStatsReporter*) + 1450
18 swift                    0x000000010c777e56 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 3494
19 swift                    0x000000010c739a30 main + 3312
20 libdyld.dylib            0x00007fff6e6589c1 start + 1
Stack dump:
0.  Program arguments: /Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2017-07-10-a.xctoolchain/usr/bin/swift -frontend -c -primary-file test2.swift -target x86_64-apple-macosx10.9 -enable-objc-interop -color-diagnostics -module-name test2 -o /var/folders/k8/7d0p_dxx2ll8vnw5mt5__ddc0000gn/T/test2-bb04db.o 
1.  While walking into decl 'S' at test2.swift:27:8
2.  While verifying FuncDecl 'f2(_:_:)' at test2.swift:33:12
3.  While verifying AbstractFunctionDecl 'f2(_:_:)' at test2.swift:33:12
<unknown>:0: error: unable to execute command: Abort trap: 6
<unknown>:0: error: compile command failed due to signal 6 (use -v to see invocation)

or this if it helps

$ ~/devel/build/Ninja-RelWithDebInfoAssert/swift-macosx-x86_64/bin/swiftc test2.swift 
Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!"), function cast, file /Users/johannes/devel/llvm/include/llvm/Support/Casting.h, line 236.
0  swift                    0x000000010a586768 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 40
1  swift                    0x000000010a5856c6 llvm::sys::RunSignalHandlers() + 86
2  swift                    0x000000010a586d2e SignalHandler(int) + 366
3  libsystem_platform.dylib 0x00007fff6e8d8f5a _sigtramp + 26
4  libsystem_platform.dylib 0x00007ffee87279a0 _sigtramp + 2045045344
5  libsystem_c.dylib        0x00007fff6e703cea abort + 127
6  libsystem_c.dylib        0x00007fff6e6cbd40 basename_r + 0
7  swift                    0x0000000108465222 (anonymous namespace)::Verifier::verifyChecked(swift::AbstractFunctionDecl*) + 818
8  swift                    0x000000010845b9da (anonymous namespace)::Verifier::walkToDeclPost(swift::Decl*) + 5482
9  swift                    0x0000000108465b14 (anonymous namespace)::Traversal::doIt(swift::Decl*) + 388
10 swift                    0x000000010846c89b (anonymous namespace)::Traversal::visitNominalTypeDecl(swift::NominalTypeDecl*) + 443
11 swift                    0x0000000108465ad6 (anonymous namespace)::Traversal::doIt(swift::Decl*) + 326
12 swift                    0x000000010846597b swift::Decl::walk(swift::ASTWalker&) + 27
13 swift                    0x00000001084f54ea swift::SourceFile::walk(swift::ASTWalker&) + 170
14 swift                    0x000000010845463b swift::verify(swift::SourceFile&) + 59
15 swift                    0x000000010825423d swift::performTypeChecking(swift::SourceFile&, swift::TopLevelContext&, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>, unsigned int, unsigned int, unsigned int, unsigned int) + 2141
16 swift                    0x0000000107f2829f swift::CompilerInstance::performSema() + 3599
17 swift                    0x0000000107518c1a performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&, swift::FrontendObserver*, swift::UnifiedStatsReporter*) + 1450
18 swift                    0x0000000107517776 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 3494
19 swift                    0x00000001074d9380 main + 3312
20 libdyld.dylib            0x00007fff6e6589c1 start + 1
21 libdyld.dylib            0x000000000000000d start + 2442819149
Stack dump:
0.  Program arguments: /Users/johannes/devel/build/Ninja-RelWithDebInfoAssert/swift-macosx-x86_64/bin/swift -frontend -c -primary-file test2.swift -target x86_64-apple-macosx10.9 -enable-objc-interop -color-diagnostics -module-name test2 -o /var/folders/k8/7d0p_dxx2ll8vnw5mt5__ddc0000gn/T/test2-c2684a.o 
1.  While walking into decl 'S' at test2.swift:27:8
2.  While verifying FuncDecl 'f2(_:_:)' at test2.swift:33:12
3.  While verifying AbstractFunctionDecl 'f2(_:_:)' at test2.swift:33:12
<unknown>:0: error: unable to execute command: Abort trap: 6
<unknown>:0: error: compile command failed due to signal 6 (use -v to see invocation)

from a very recent swiftc on master (the one from #11040

The text was updated successfully, but these errors were encountered:

weissi · 2017-07-24T19:02:05Z

slightly smaller repro

public struct Foo<A, B> {}

public protocol P {
    associatedtype PA
    associatedtype PB = Never

    typealias Context = Foo<PA, PB>

    func f1(_ x: Context, _ y: PA)
    func f2(_ x: Context, _ y: PB)
}

public struct S: P {
    public typealias PA = Never

    public func f1(_ x: Context, _ y: PA) {
    }
    public func f2(_ x: Context, _ y: PB) {
    }
}

weissi · 2017-07-25T12:09:54Z

@swift-ci create

slavapestov · 2017-07-26T23:39:28Z

Even smaller repro:

public protocol P {
    associatedtype PC = Never

    func f2(_ x: PC)
}

public struct S: P {
    public func f1(_ x: PC) {
    }

    public func f2(_ x: PC) {
    }

}

It works if you switch the order of f1 and f2 inside struct S, but for the wrong reason.

slavapestov · 2017-07-26T23:45:59Z

Hi @weissi, my suggested workaround would be to explicitly define the associated types as typealiases inside the concrete type, instead of relying on associated type inference. It is unlikely we'll be able to fix this for 4.0, at least not in a general way.

slavapestov · 2017-07-26T23:48:27Z

Also tested in 3.1, it also crashes as I suspected, just a little bit later because the AST verifier is not compiled in.

slavapestov · 2017-07-27T00:03:16Z

In getWitnessTypeForMatching(), the hasValidSignature() check should be an assertion, instead of silently bailing out:

  if (witness->isInvalid() || !witness->hasValidSignature())
    return Type();

weissi · 2017-11-29T11:42:41Z

@slavapestov with the Swift 4.1 dev snapshot from today both your and my reduced repro doesn't work anymore. The attached test2.swift still reproes though.

gregomni · 2018-10-14T05:45:22Z

Fix for linked SR-8813 turns out to fix this as well.

swift-ci transferred this issue from apple/swift-issues Apr 25, 2022

AnthonyLatsis added the crash Bug: A crash, i.e., an abnormal termination of software label Dec 12, 2022

AnthonyLatsis mentioned this issue Nov 17, 2023

[SR-6516] error: reference to invalid associated type 'Context' of type 'S' #49066

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[SR-5546] Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!") #48118

[SR-5546] Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!") #48118

weissi commented Jul 24, 2017

weissi commented Jul 24, 2017

weissi commented Jul 25, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 27, 2017

weissi commented Nov 29, 2017

gregomni commented Oct 14, 2018

[SR-5546] Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!") #48118

[SR-5546] Assertion failed: (isa<X>(Val) && "cast<Ty>() argument of incompatible type!") #48118

Comments

weissi commented Jul 24, 2017

weissi commented Jul 24, 2017

weissi commented Jul 25, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 26, 2017

slavapestov commented Jul 27, 2017

weissi commented Nov 29, 2017

gregomni commented Oct 14, 2018