[SR-4487] Crash when pattern matching two cases with associated values of protocol type

[rxwei]

Previous ID	SR-4487
Radar	None
Original Reporter	@rxwei
Type	Bug
Status	Resolved
Resolution	Duplicate

Environment

3.1

Additional Detail from JIRA

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

md5: a545da02adca998e1913031050b3b288

duplicates:

• SR-4439 Compiler crashes when chaining case statements that capture values with weak references

Issue Description:

Crash:

protocol Foo {
}

enum Bar {
    case aaa(Foo)
    case bbb(Foo)
}

func acceptBar(_ x: Bar) {  /// Crash here
    switch x {
    case let .aaa(f),
         let .bbb(f):
        break
    }
}

No crash if switch written as

func acceptBar(_ x: Bar) {
    switch x {
    case let .aaa(f): break
    case let .bbb(f): break
    }
}

0  swift                    0x00000001123deeb7 PrintStackTraceSignalHandler(void*) + 39
1  swift                    0x00000001123de366 SignalHandler(int) + 646
2  libsystem_platform.dylib 0x00007fff8fa31b3a _sigtramp + 26
3  libsystem_platform.dylib 0x0000000000000002 _sigtramp + 1885136098
4  swift                    0x000000010fe307be (anonymous namespace)::TypeClassifierBase<(anonymous namespace)::LowerType, swift::Lowering::TypeLowering const*>::visitExistentialType(swift::CanType) + 30
5  swift                    0x000000010fe2fadc swift::Lowering::TypeConverter::getTypeLoweringForUncachedLoweredType(swift::Lowering::TypeConverter::TypeKey) + 76
6  swift                    0x000000010fe2f318 swift::Lowering::TypeConverter::getTypeLowering(swift::Lowering::AbstractionPattern, swift::Type, unsigned int) + 2328
7  swift                    0x000000010fa52413 swift::Lowering::emitBeginVarargs(swift::Lowering::SILGenFunction&, swift::SILLocation, swift::CanType, swift::CanType, unsigned int) + 675
8  swift                    0x000000010f9fbfc1 (anonymous namespace)::ArgEmitter::emitShuffle(swift::Expr*, swift::Expr*, llvm::ArrayRef<swift::TupleTypeElt>, swift::ConcreteDeclRef, llvm::ArrayRef<swift::Expr*>, llvm::ArrayRef<int>, llvm::ArrayRef<unsigned int>, swift::Type, swift::Lowering::AbstractionPattern) + 2145
9  swift                    0x000000010f9fa676 (anonymous namespace)::ArgEmitter::emitExpanded(swift::Lowering::ArgumentSource&&, swift::Lowering::AbstractionPattern) + 1958
10 swift                    0x000000010f9f7bde (anonymous namespace)::ArgEmitter::emit(swift::Lowering::ArgumentSource&&, swift::Lowering::AbstractionPattern) + 286
11 swift                    0x000000010f9f7246 (anonymous namespace)::CallSite::emit(swift::Lowering::SILGenFunction&, swift::Lowering::AbstractionPattern, (anonymous namespace)::ParamLowering&, llvm::SmallVectorImpl<swift::Lowering::ManagedValue>&, llvm::SmallVectorImpl<std::__1::pair<swift::Lowering::LValue, swift::SILLocation> >&, llvm::Optional<swift::ForeignErrorConvention> const&, swift::ImportAsMemberStatus const&) && + 438
12 swift                    0x000000010f9f459b (anonymous namespace)::CallEmission::apply(swift::Lowering::SGFContext) + 6123
13 swift                    0x000000010fa402ec swift::ASTVisitor<(anonymous namespace)::RValueEmitter, swift::Lowering::RValue, void, void, void, void, void, swift::Lowering::SGFContext>::visit(swift::Expr*, swift::Lowering::SGFContext) + 124
14 swift                    0x000000010fa9db73 swift::Lowering::SILGenFunction::emitReturnExpr(swift::SILLocation, swift::Expr*) + 467
15 swift                    0x000000010fa99acc swift::ASTVisitor<(anonymous namespace)::StmtEmitter, void, void, void, void, void, void>::visit(swift::Stmt*) + 188
16 swift                    0x000000010fa9d268 swift::ASTVisitor<(anonymous namespace)::StmtEmitter, void, void, void, void, void, void>::visit(swift::Stmt*) + 14424
17 swift                    0x000000010fa798ca void llvm::function_ref<void ((anonymous namespace)::PatternMatchEmission&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, (anonymous namespace)::ClauseRow&)>::callback_fn<swift::Lowering::SILGenFunction::emitSwitchStmt(swift::SwitchStmt*)::$_1>(long, (anonymous namespace)::PatternMatchEmission&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, (anonymous namespace)::ClauseRow&) + 458
18 swift                    0x000000010fa7b040 (anonymous namespace)::PatternMatchEmission::emitDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, std::__1::function<void (swift::SILLocation)> const&) + 4448
19 swift                    0x000000010fa82973 std::__1::__function::__func<(anonymous namespace)::PatternMatchEmission::emitSpecializedDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, unsigned int&, unsigned int, std::__1::function<void (swift::SILLocation)> const&)::$_7, std::__1::allocator<(anonymous namespace)::PatternMatchEmission::emitSpecializedDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, unsigned int&, unsigned int, std::__1::function<void (swift::SILLocation)> const&)::$_7>, void (llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, llvm::ArrayRef<(anonymous namespace)::SpecializedRow>, std::__1::function<void (swift::SILLocation)> const&)>::operator()(llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>&&, llvm::ArrayRef<(anonymous namespace)::SpecializedRow>&&, std::__1::function<void (swift::SILLocation)> const&) + 3219
20 swift                    0x000000010fa7e9e0 (anonymous namespace)::PatternMatchEmission::emitDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, std::__1::function<void (swift::SILLocation)> const&) + 19200
21 swift                    0x000000010fa82973 std::__1::__function::__func<(anonymous namespace)::PatternMatchEmission::emitSpecializedDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, unsigned int&, unsigned int, std::__1::function<void (swift::SILLocation)> const&)::$_7, std::__1::allocator<(anonymous namespace)::PatternMatchEmission::emitSpecializedDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, unsigned int&, unsigned int, std::__1::function<void (swift::SILLocation)> const&)::$_7>, void (llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, llvm::ArrayRef<(anonymous namespace)::SpecializedRow>, std::__1::function<void (swift::SILLocation)> const&)>::operator()(llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>&&, llvm::ArrayRef<(anonymous namespace)::SpecializedRow>&&, std::__1::function<void (swift::SILLocation)> const&) + 3219
22 swift                    0x000000010fa7d294 (anonymous namespace)::PatternMatchEmission::emitDispatch((anonymous namespace)::ClauseMatrix&, llvm::ArrayRef<swift::Lowering::ConsumableManagedValue>, std::__1::function<void (swift::SILLocation)> const&) + 13236
23 swift                    0x000000010fa790a3 swift::Lowering::SILGenFunction::emitSwitchStmt(swift::SwitchStmt*) + 2419
24 swift                    0x000000010fa9d268 swift::ASTVisitor<(anonymous namespace)::StmtEmitter, void, void, void, void, void, void>::visit(swift::Stmt*) + 14424
25 swift                    0x000000010fa5c979 swift::Lowering::SILGenFunction::emitFunction(swift::FuncDecl*) + 409
26 swift                    0x000000010f9ddd2b swift::Lowering::SILGenModule::emitFunction(swift::FuncDecl*)::$_1::operator()(swift::SILFunction*) const + 1867
27 swift                    0x000000010f9dc902 swift::Lowering::SILGenModule::emitFunction(swift::FuncDecl*) + 642
28 swift                    0x000000010faa357a swift::Lowering::SILGenModule::visitExtensionDecl(swift::ExtensionDecl*) + 634
29 swift                    0x000000010f9ea33b swift::Lowering::SILGenModule::emitSourceFile(swift::SourceFile*, unsigned int) + 1483
30 swift                    0x000000010f9ebf19 swift::SILModule::constructSIL(swift::ModuleDecl*, swift::SILOptions&, swift::FileUnit*, llvm::Optional<unsigned int>, bool, bool) + 1593
31 swift                    0x000000010f1fe0b2 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 42402
32 swift                    0x000000010f1ad88c main + 9052
33 libdyld.dylib            0x00007fff8f822235 start + 1

[rxwei]

Duped