[SR-13732] Type checker crash-on-invalid

[dabrahams]

Previous ID	SR-13732
Radar	rdar://problem/70338668
Original Reporter	@dabrahams
Type	Bug
Status	Resolved
Resolution	Done

Additional Detail from JIRA

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

md5: b7018e1dfe9bea2bf0043ad3021a54a0

Issue Description:

Compile:

extension MutableCollection {
  public mutating func writePrefix<I: IteratorProtocol>(from source: inout I)
    -> (writtenCount: Int, afterLastWritten: Index)
    where I.Element == Element
  {
    fatalError()
  }
  
  public mutating func writePrefix<Source: Collection>(from source: Source)
    -> (writtenCount: Int, afterLastWritten: Index, afterLastRead: Source.Index)
    where Source.Element == Element
  {
    fatalError()
  }

}

func testWritePrefixIterator() {
  var a = Array(0..<10)
  
  var underflow = (1..<10).makeIterator()
  var (writtenCount, afterLastWritten) = a.writePrefix(from: underflow)
}

0.  Program arguments: /Applications/Xcode-beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift -frontend -c -primary-file x.swift -target x86_64-apple-darwin19.6.0 -enable-objc-interop -stack-check -sdk /Applications/Xcode-beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX11.0.sdk -target-sdk-version 11.0 -module-name x -o /var/folders/z0/4612twmx5wbfrsp0jxbcvwrm00qbwx/T/x-69a4f6.o 
1.  Apple Swift version 5.3 (swiftlang-1200.0.28.1 clang-1200.0.30.1)
2.  While evaluating request TypeCheckSourceFileRequest(source_file "x.swift")
3.  While evaluating request TypeCheckFunctionBodyUntilRequest(x.(file).testWritePrefixIterator()@x.swift:18:8, )
4.  While type-checking statement at [x.swift:18:34 - line:23:3] RangeText="{
    var a = Array(0..<10)
    
    var underflow = (1..<10).makeIterator()
    var (writtenCount, afterLastWritten) = a.writePrefix(from: underflow)
  "
5.  While type-checking declaration 0x7fec7703dc70 (at x.swift:22:5)
6.  While evaluating request PatternBindingEntryRequest((unknown decl), 0)
7.  While type-checking expression at [x.swift:22:44 - line:22:73] RangeText="a.writePrefix(from: underflow"
0  swift                    0x0000000109f64a85 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 37
1  swift                    0x0000000109f63a85 llvm::sys::RunSignalHandlers() + 85
2  swift                    0x0000000109f6503f SignalHandler(int) + 111
3  libsystem_platform.dylib 0x00007fff67c7a5fd _sigtramp + 29
4  swift                    0x00000001068bec1f swift::Type llvm::function_ref<swift::Type (swift::TypeVariableType*)>::callback_fn<swift::constraints::ConstraintSystem::simplifyType(swift::Type) const::$_18>(long, swift::TypeVariableType*) + 47
5  swift                    0x000000010680de64 swift::constraints::ConstraintSystem::simplifyFixConstraint(swift::constraints::ConstraintFix*, swift::Type, swift::Type, swift::constraints::ConstraintKind, swift::OptionSet<swift::constraints::ConstraintSystem::TypeMatchFlags, unsigned int>, swift::constraints::ConstraintLocatorBuilder) + 2628
6  swift                    0x00000001067fb0ce swift::constraints::ConstraintSystem::matchTypes(swift::Type, swift::Type, swift::constraints::ConstraintKind, swift::OptionSet<swift::constraints::ConstraintSystem::TypeMatchFlags, unsigned int>, swift::constraints::ConstraintLocatorBuilder) + 15134
7  swift                    0x00000001068216f7 swift::constraints::ConstraintSystem::simplifyConstraint(swift::constraints::Constraint const&) + 2119
8  swift                    0x000000010682cd31 swift::constraints::ConstraintSystem::simplify(bool) + 145
9  swift                    0x0000000106842232 swift::constraints::DisjunctionStep::attempt(swift::constraints::DisjunctionChoice const&) + 178
10 swift                    0x0000000106841a8c swift::constraints::BindingStep<swift::constraints::DisjunctionChoiceProducer>::take(bool) + 540
11 swift                    0x0000000106841855 swift::constraints::DisjunctionStep::resume(bool) + 821
12 swift                    0x000000010682ece7 swift::constraints::ConstraintSystem::solveImpl(llvm::SmallVectorImpl<swift::constraints::Solution>&) + 311
13 swift                    0x00000001068b1519 swift::constraints::ConstraintSystem::salvage() + 185
14 swift                    0x000000010683134d swift::constraints::ConstraintSystem::solve(swift::constraints::SolutionApplicationTarget&, swift::FreeTypeVariableBinding) + 1821
15 swift                    0x000000010696ed5f swift::TypeChecker::typeCheckExpression(swift::constraints::SolutionApplicationTarget&, bool&, swift::OptionSet<swift::TypeCheckExprFlags, unsigned int>) + 799
16 swift                    0x00000001069704d7 swift::TypeChecker::typeCheckBinding(swift::Pattern*&, swift::Expr*&, swift::DeclContext*, swift::Type, swift::PatternBindingDecl*, unsigned int) + 151
17 swift                    0x00000001069706c0 swift::TypeChecker::typeCheckPatternBinding(swift::PatternBindingDecl*, unsigned int, swift::Type) + 256
18 swift                    0x0000000106a59006 swift::PatternBindingEntryRequest::evaluate(swift::Evaluator&, swift::PatternBindingDecl*, unsigned int) const + 550
19 swift                    0x000000010699faa9 llvm::Expected<swift::PatternBindingEntryRequest::OutputType> swift::Evaluator::getResultUncached<swift::PatternBindingEntryRequest>(swift::PatternBindingEntryRequest const&) + 777
20 swift                    0x0000000106991a77 swift::PatternBindingEntryRequest::OutputType swift::evaluateOrDefault<swift::PatternBindingEntryRequest>(swift::Evaluator&, swift::PatternBindingEntryRequest, swift::PatternBindingEntryRequest::OutputType) + 55
21 swift                    0x00000001069c5a1f (anonymous namespace)::DeclChecker::visit(swift::Decl*) + 5007
22 swift                    0x0000000106a53ca7 swift::ASTVisitor<(anonymous namespace)::StmtChecker, void, swift::Stmt*, void, void, void, void>::visit(swift::Stmt*) + 8695
23 swift                    0x0000000106a4f69a bool (anonymous namespace)::StmtChecker::typeCheckStmt<swift::BraceStmt>(swift::BraceStmt*&) + 314
24 swift                    0x0000000106a4e0a7 swift::TypeCheckFunctionBodyUntilRequest::evaluate(swift::Evaluator&, swift::AbstractFunctionDecl*, swift::SourceLoc) const + 2231
25 swift                    0x0000000106a56e7d llvm::Expected<swift::TypeCheckFunctionBodyUntilRequest::OutputType> swift::Evaluator::getResultCached<swift::TypeCheckFunctionBodyUntilRequest, (void*)0>(swift::TypeCheckFunctionBodyUntilRequest const&) + 925
26 swift                    0x0000000106a4f148 swift::TypeCheckFunctionBodyUntilRequest::OutputType swift::evaluateOrDefault<swift::TypeCheckFunctionBodyUntilRequest>(swift::Evaluator&, swift::TypeCheckFunctionBodyUntilRequest, swift::TypeCheckFunctionBodyUntilRequest::OutputType) + 440
27 swift                    0x0000000106a8ca84 swift::TypeCheckSourceFileRequest::evaluate(swift::Evaluator&, swift::SourceFile*) const + 1380
28 swift                    0x0000000106a8f699 llvm::Expected<swift::TypeCheckSourceFileRequest::OutputType> swift::Evaluator::getResultUncached<swift::TypeCheckSourceFileRequest>(swift::TypeCheckSourceFileRequest const&) + 953
29 swift                    0x0000000106a8c394 swift::TypeCheckSourceFileRequest::OutputType swift::evaluateOrDefault<swift::TypeCheckSourceFileRequest>(swift::Evaluator&, swift::TypeCheckSourceFileRequest, swift::TypeCheckSourceFileRequest::OutputType) + 164
30 swift                    0x0000000105c07a07 swift::CompilerInstance::performSemaUpTo(swift::SourceFile::ASTStage_t) + 6439
31 swift                    0x0000000105ac896d swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 6845
32 swift                    0x0000000105a4d277 main + 1255
33 libdyld.dylib            0x00007fff67a81cc9 start + 1
34 libdyld.dylib            0x0000000000000011 start + 18446603338777092937

[typesanitizer]

@swift-ci create

[LucianoPAlmeida]

Fixed on main #34330
@dabrahams Can you please verify on next available snapshot. Thanks