Parameter packs for functions with arbitrary parameters causes compiler crash when passed a function with more than zero parameters

[twof]

Description

I'm trying to use parameter packs to create a function that takes and arbitrary function as a parameter. It's possible to create that function, but it's not possible to call it with a function or closure that has any parameters. Doing so causes the compiler to crash.

Stack trace passing a function with a parameter:

0.	Program arguments: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift-frontend -frontend -c /Users/fnord/Documents/Swift/TestMacOS/TestMacOSCore/Sources/TestMacOSCore/Dependencies.swift -primary-file /Users/fnord/Documents/Swift/TestMacOS/TestMacOSCore/Sources/TestMacOSCore/TestMacOSCore.swift -emit-dependencies-path /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.d -emit-const-values-path /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.swiftconstvalues -emit-reference-dependencies-path /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.swiftdeps -serialize-diagnostics-path /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.dia -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/MacOSX14.0.sdk -I /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug -I /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/usr/lib -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/PackageFrameworks -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/PackageFrameworks -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/PackageFrameworks -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/PackageFrameworks -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/PackageFrameworks -F /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug -F /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/Library/Frameworks -no-color-diagnostics -enable-testing -g -module-cache-path /Users/fnord/Library/Developer/Xcode/DerivedData/ModuleCache.noindex -profile-generate -profile-coverage-mapping -swift-version 5 -enforce-exclusivity=checked -Onone -D SWIFT_PACKAGE -D DEBUG -D Xcode -serialize-debugging-options -package-name testmacoscore -const-gather-protocols-file /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore_const_extract_protocols.json -empty-abi-descriptor -validate-clang-modules-once -clang-build-session-file /Users/fnord/Library/Developer/Xcode/DerivedData/ModuleCache.noindex/Session.modulevalidation -Xcc -working-directory -Xcc /Users/fnord/Documents/Swift/TestMacOS/TestMacOSCore -resource-dir /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift -enable-anonymous-context-mangled-names -Xcc -ivfsstatcache -Xcc /Users/fnord/Library/Developer/Xcode/DerivedData/SDKStatCaches.noindex/macosx14.0-23A334-4a76ee93ef69e462914ffe9883de22b8.sdkstatcache -Xcc -I/Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/swift-overrides.hmap -Xcc -I/Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Products/Debug/include -Xcc -I/Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/DerivedSources-normal/arm64 -Xcc -I/Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/DerivedSources/arm64 -Xcc -I/Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/DerivedSources -Xcc -DSWIFT_PACKAGE -Xcc -DDEBUG=1 -module-name TestMacOSCore -frontend-parseable-output -disable-clang-spi -target-sdk-version 14.0 -target-sdk-name macosx14.0 -external-plugin-path /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.0.sdk/usr/lib/swift/host/plugins#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.0.sdk/usr/bin/swift-plugin-server -external-plugin-path /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.0.sdk/usr/local/lib/swift/host/plugins#/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.0.sdk/usr/bin/swift-plugin-server -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 -o /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Build/Intermediates.noindex/TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.o -index-unit-output-path /TestMacOSCore.build/Debug/TestMacOSCore.build/Objects-normal/arm64/TestMacOSCore.o -index-store-path /Users/fnord/Library/Developer/Xcode/DerivedData/TestMacOSCore-ahgngaarecknxsfwsewfijgzqaot/Index.noindex/DataStore -index-system-modules
1.	Apple Swift version 5.9 (swiftlang-5.9.0.128.108 clang-1500.0.40.1)
2.	Compiling with the current language version
3.	While evaluating request ExecuteSILPipelineRequest(Run pipelines { Mandatory Diagnostic Passes + Enabling Optimization Passes } on SIL for TestMacOSCore)
4.	While running pass #20 SILModuleTransform "DiagnoseStaticExclusivity".
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           0x0000000107ac314c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56
1  swift-frontend           0x000000010a641f2c llvm::sys::RunSignalHandlers() + 112
2  swift-frontend           0x000000010638310c SignalHandler(int) + 352
3  libsystem_platform.dylib 0x0000000184841a24 _sigtramp + 56
4  swift-frontend           0x000000010987d8c4 checkForViolationAtApply(swift::ApplySite, (anonymous namespace)::AccessState&) + 544
5  swift-frontend           0x000000010987d8c4 checkForViolationAtApply(swift::ApplySite, (anonymous namespace)::AccessState&) + 544
6  swift-frontend           0x000000010986f1d8 (anonymous namespace)::DiagnoseStaticExclusivity::run() (.llvm.4864455472777275936) + 2220
7  swift-frontend           0x0000000109f9b08c swift::SILPassManager::executePassPipelinePlan(swift::SILPassPipelinePlan const&) + 16276
8  swift-frontend           0x000000010a11ef90 swift::SimpleRequest<swift::ExecuteSILPipelineRequest, std::__1::tuple<> (swift::SILPipelineExecutionDescriptor), (swift::RequestFlags)1>::evaluateRequest(swift::ExecuteSILPipelineRequest const&, swift::Evaluator&) + 56
9  swift-frontend           0x0000000109fd47e4 llvm::Expected<swift::ExecuteSILPipelineRequest::OutputType> swift::Evaluator::getResultUncached<swift::ExecuteSILPipelineRequest>(swift::ExecuteSILPipelineRequest const&) + 476
10 swift-frontend           0x0000000109fef728 swift::runSILDiagnosticPasses(swift::SILModule&) + 380
11 swift-frontend           0x0000000105a99f58 swift::CompilerInstance::performSILProcessing(swift::SILModule*) + 72
12 swift-frontend           0x0000000109ed7328 performCompileStepsPostSILGen(swift::CompilerInstance&, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>>, llvm::PointerUnion<swift::ModuleDecl*, swift::SourceFile*>, swift::PrimarySpecificPaths const&, int&, swift::FrontendObserver*) + 956
13 swift-frontend           0x000000010a5f991c performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1748
14 swift-frontend           0x000000010a5fd474 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 4568
15 swift-frontend           0x0000000109f434e0 swift::mainEntry(int, char const**) + 4116
16 dyld                     0x0000000184499058 start + 2224

Steps to reproduce

This builds

func catFact() -> String { "there are more than 10 cats" }

func callable<each Input, Output>(wrappedValue: @escaping ((repeat each Input)) -> Output) {
  
}

func doSomething() {
  callable(wrappedValue: catFact)
}

This builds

func callable<each Input, Output>(wrappedValue: @escaping ((repeat each Input)) -> Output) {
  
}

func doSomething() {
  callable(wrappedValue: {})
}

This does not build

func catFact(num: Int) -> String { "there are more than 10 cats" }

func callable<each Input, Output>(wrappedValue: @escaping ((repeat each Input)) -> Output) {
  
}

func doSomething() {
  callable(wrappedValue: catFact)
}

This does not build

func callable<each Input, Output>(wrappedValue: @escaping ((repeat each Input)) -> Output) {
  
}

func doSomething() {
  callable(wrappedValue: { (num: Int) in num })
}

Expected behavior

I would expect each of the above examples to build successfully.

Environment

• Swift compiler version info:

swift-driver version: 1.87.1 Apple Swift version 5.9 (swiftlang-5.9.0.128.108 clang-1500.0.40.1)
Target: arm64-apple-macosx14.0

• Xcode version info

Xcode 15.0
Build version 15A240d

• Deployment target: macOS 14.0

• Additional context: Development is being done in a Swift Package using Xcode.

[CodPro-Sui]

// Define a function that takes a closure with variadic parameters
func processVariadicFunction(_ function: (Int...) -> Int) {
    // Create an array of integers
    let numbers = [1, 2, 3, 4, 5]
    
    // Call the closure with the array as variadic arguments
    let result = function(numbers[0], numbers[1], numbers[2], numbers[3], numbers[4])
    
    // Print the result
    print("Result: \(result)")
}

// Define a closure that calculates the sum of integers
let sumClosure: (Int...) -> Int = { numbers in
    return numbers.reduce(0, +)
}

// Call the processVariadicFunction with the sumClosure
processVariadicFunction(sumClosure)

[twof]

@Nau56 That's different from what I'm trying to do. Your example uses a variadic parameter, and mine uses a parameter pack.

[CodPro-Sui]

typealias MyFunctionPointer = (Int, Int) -> Void

func bar(func: MyFunctionPointer) {
  func(1, 2)
}

let myFunction: MyFunctionPointer = { a, b in
  print(a + b)
}

bar(func: myFunction)

[twof]

@Nau56 Sorry I'm not sure what that's supposed to be.