Compiler crash when returning a throwing closure with typed Error set to Never

[martialln]

Description

While I was playing with the memoization code seen in the forum to add support for typed error, I encountered a crash in the compiler.

I reduce it to the fact that the compiler crash when trying to return a throwing closure with typed error.

Reproduction

func bar<Err: Error>(
    _ f: @escaping () throws(Err) -> Void
) -> () throws(Err) -> Void {
    return {
        print("call f")
        return try f()
    }
}

let f = { print("hu?") }
let bared = bar(f)

Stack dump

0.	Program arguments: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-frontend -frontend -emit-module -experimental-skip-non-inlinable-function-bodies-without-types <PROJECT_PATH>/memoize/Sources/main.swift -target arm64-apple-macos14.0 -Xllvm -aarch64-use-tbi -enable-objc-interop -stack-check -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX15.2.sdk -I <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Products/Debug -I /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -F <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Products/Debug -F /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -no-color-diagnostics -enable-testing -g -debug-info-format=dwarf -dwarf-version=4 -module-cache-path <HOME>/Library/Developer/Xcode/DerivedData/ModuleCache.noindex -swift-version 6 -enforce-exclusivity=checked -Onone -D SWIFT_PACKAGE -D DEBUG -D Xcode -serialize-debugging-options -const-gather-protocols-file <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize_const_extract_protocols.json -enable-experimental-feature DebugDescriptionMacro -enable-experimental-feature OpaqueTypeErasure -empty-abi-descriptor -plugin-path /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins/testing -validate-clang-modules-once -clang-build-session-file <HOME>/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc <PROJECT_PATH>/memoize/.swiftpm/xcode -resource-dir /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift -enable-anonymous-context-mangled-names -file-compilation-dir <PROJECT_PATH>/memoize/.swiftpm/xcode -Xcc -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_DEBUG -Xcc -ivfsstatcache -Xcc <HOME>/Library/Developer/Xcode/DerivedData/SDKStatCaches.noindex/macosx15.2-24C94-1dd28740b163f220e3e9b9fd2a542f53.sdkstatcache -Xcc -I<HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Products/Debug/include -Xcc -I<HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/DerivedSources-normal/arm64 -Xcc -I<HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/DerivedSources/arm64 -Xcc -I<HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/DerivedSources -Xcc -DSWIFT_PACKAGE -Xcc -DDEBUG=1 -module-name memoize -package-name memoize -frontend-parseable-output -disable-clang-spi -target-sdk-version 15.2 -target-sdk-name macosx15.2 -external-plugin-path /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib/swift/host/plugins#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server -external-plugin-path /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/local/lib/swift/host/plugins#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/bin/swift-plugin-server -plugin-path /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/host/plugins -plugin-path /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/local/lib/swift/host/plugins -emit-module-doc-path <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize.swiftdoc -emit-module-source-info-path <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize.swiftsourceinfo -serialize-diagnostics-path <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize-master-emit-module.dia -emit-dependencies-path <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize-master-emit-module.d -o <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize.swiftmodule -emit-abi-descriptor-path <HOME>/Library/Developer/Xcode/DerivedData/memoize-gsgovrbqeiyawbbpnzjqtjnokvkg/Build/Intermediates.noindex/memoize.build/Debug/memoize.build/Objects-normal/arm64/memoize.abi.json
1.	Apple Swift version 6.0.3 (swiftlang-6.0.3.1.10 clang-1600.0.30.1)
2.	Compiling with the current language version
3.	While evaluating request ASTLoweringRequest(Lowering AST to SIL for module memoize)
4.	While emitting reabstraction thunk in SIL function "@$ss5NeverOIegzr_Ieg_TR".
 for <<debugloc at "<compiler-generated>":0:0>>Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
0  swift-frontend           0x000000010a94aa9c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56
1  swift-frontend           0x000000010a948cf0 llvm::sys::RunSignalHandlers() + 112
2  swift-frontend           0x000000010a94b068 SignalHandler(int) + 292
3  libsystem_platform.dylib 0x0000000191dbae04 _sigtramp + 56
4  swift-frontend           0x0000000105d1f2a0 swift::Lowering::SILGenFunction::emitApplyWithRethrow(swift::SILLocation, swift::SILValue, swift::SILType, swift::SubstitutionMap, llvm::ArrayRef<swift::SILValue>) + 2288
5  swift-frontend           0x0000000105e2b364 buildThunkBody(swift::Lowering::SILGenFunction&, swift::SILLocation, swift::Lowering::AbstractionPattern, swift::CanTypeWrapper<swift::AnyFunctionType>, swift::Lowering::AbstractionPattern, swift::CanTypeWrapper<swift::AnyFunctionType>, swift::CanTypeWrapper<swift::SILFunctionType>, swift::CanType, llvm::function_ref<void (swift::Lowering::SILGenFunction&)>) + 1988
6  swift-frontend           0x0000000105e2d1c4 createThunk(swift::Lowering::SILGenFunction&, swift::SILLocation, swift::Lowering::ManagedValue, swift::Lowering::AbstractionPattern, swift::CanTypeWrapper<swift::AnyFunctionType>, swift::Lowering::AbstractionPattern, swift::CanTypeWrapper<swift::AnyFunctionType>, swift::Lowering::TypeLowering const&) + 3840
7  swift-frontend           0x0000000105e228fc (anonymous namespace)::Transform::transform(swift::Lowering::ManagedValue, swift::Lowering::AbstractionPattern, swift::CanType, swift::Lowering::AbstractionPattern, swift::CanType, swift::SILType, swift::Lowering::SGFContext) + 1700
8  swift-frontend           0x0000000105d737a4 swift::Lowering::Conversion::emit(swift::Lowering::SILGenFunction&, swift::SILLocation, swift::Lowering::ManagedValue, swift::Lowering::SGFContext) const + 472
9  swift-frontend           0x0000000105cfd5f8 (anonymous namespace)::ScalarResultPlan::finish(swift::Lowering::SILGenFunction&, swift::SILLocation, swift::Lowering::ManagedValue, swift::Lowering::AbstractionPattern, swift::CanType, swift::Lowering::Initialization*, swift::SILFunctionTypeRepresentation) + 692
10 swift-frontend           0x0000000105cfd200 (anonymous namespace)::ScalarResultPlan::finish(swift::Lowering::SILGenFunction&, swift::SILLocation, llvm::ArrayRef<swift::Lowering::ManagedValue>&, swift::SILValue) + 440
11 swift-frontend           0x0000000105d1e29c swift::Lowering::SILGenFunction::emitApply(std::__1::unique_ptr<swift::Lowering::ResultPlan, std::__1::default_delete<swift::Lowering::ResultPlan>>&&, swift::Lowering::ArgumentScope&&, swift::SILLocation, swift::Lowering::ManagedValue, swift::SubstitutionMap, llvm::ArrayRef<swift::Lowering::ManagedValue>, swift::Lowering::CalleeTypeInfo const&, swift::optionset::OptionSet<swift::ApplyFlags, unsigned char>, swift::Lowering::SGFContext, std::__1::optional<swift::ActorIsolation>) + 3344
12 swift-frontend           0x0000000105d24f50 (anonymous namespace)::CallEmission::apply(swift::Lowering::SGFContext) + 2240
13 swift-frontend           0x0000000105d23408 swift::Lowering::SILGenFunction::emitApplyExpr(swift::ApplyExpr*, swift::Lowering::SGFContext) + 3116
14 swift-frontend           0x0000000105d9037c swift::Lowering::SILGenFunction::emitExprInto(swift::Expr*, swift::Lowering::Initialization*, std::__1::optional<swift::SILLocation>) + 128
15 swift-frontend           0x0000000105d7b90c swift::Lowering::SILGenFunction::emitPatternBinding(swift::PatternBindingDecl*, unsigned int, bool) + 2016
16 swift-frontend           0x0000000105d82840 swift::ASTVisitor<swift::Lowering::SILGenFunction, void, void, void, void, void, void>::visit(swift::Decl*) + 140
17 swift-frontend           0x0000000105e5b638 swift::ASTVisitor<swift::Lowering::SILGenTopLevel, void, void, void, void, void, void>::visit(swift::Decl*) + 2132
18 swift-frontend           0x0000000105e5895c swift::Lowering::SILGenModule::emitEntryPoint(swift::SourceFile*, swift::SILFunction*) + 1472
19 swift-frontend           0x0000000105d12ec0 swift::ASTLoweringRequest::evaluate(swift::Evaluator&, swift::ASTLoweringDescriptor) const + 1428
20 swift-frontend           0x0000000105e4992c swift::SimpleRequest<swift::ASTLoweringRequest, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>> (swift::ASTLoweringDescriptor), (swift::RequestFlags)9>::evaluateRequest(swift::ASTLoweringRequest const&, swift::Evaluator&) + 196
21 swift-frontend           0x0000000105d17f14 swift::ASTLoweringRequest::OutputType swift::Evaluator::getResultUncached<swift::ASTLoweringRequest, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'()>(swift::ASTLoweringRequest const&, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'()) + 528
22 swift-frontend           0x00000001052f2304 swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 2828
23 swift-frontend           0x00000001052f4e88 performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1684
24 swift-frontend           0x00000001052f3bb4 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 3572
25 swift-frontend           0x000000010527aa5c swift::mainEntry(int, char const**) + 3680
26 dyld                     0x0000000191a04274 start + 2840

Expected behavior

The compiler doesn't crash.

Environment

swift-driver version: 1.115.1 Apple Swift version 6.0.3 (swiftlang-6.0.3.1.10 clang-1600.0.30.1)
Target: arm64-apple-macosx15.0

Additional information

Returning the same throwing closure with untyped error works.

[martialln]

Maybe a duplicate of #74273