Assertion failed: (genericSig && "Need a generic signature to resolve conformance")

[fibrechannelscsi]

Description

The compiler crashes when compiling the code listed below in Debug mode.
The full assertion is:
Assertion failed: (genericSig && "Need a generic signature to resolve conformance"), function appendAnyProtocolConformance, file ASTMangler.cpp, line 4151.

Reproduction

This reproducer requires one public import: swift-collections. A sample Package.swift file is enclosed below.

import Foundation; import OrderedCollections; import _Differentiation
extension OrderedDictionary: Differentiable where Value: Differentiable {
    public typealias TangentVector = OrderedDictionary<Key, Value.TangentVector>
    public mutating func move(by direction: TangentVector) {}
}
extension OrderedDictionary: AdditiveArithmetic where Value: AdditiveArithmetic {
    public static func + (_ lhs: Self, _ rhs: Self) -> Self {fatalError()}
    public static func - (_ lhs: Self, _ rhs: Self) -> Self {fatalError()}
    public static var zero: Self { [:] }
}
struct A<I: Hashable, D: Differentiable>: Differentiable {
    var r: OrderedDictionary<I, OrderedDictionary<String, D>>
    @differentiable(reverse) mutating func i(x: I, v: OrderedDictionary<String, D>) {self.r[x] = v}
}

Package.swift:

import PackageDescription
let package = Package(
    name: "70000",
    dependencies: [.package(url: "https://github.com/apple/swift-collections.git", from: "1.0.0")],
    targets: [.executableTarget(name: "70000", dependencies: [.product(name: "Collections", package: "swift-collections")])]
)

Expected behavior

The compilation should succeed. Or, the compiler should produce an error message as to why the compilation cannot succeed.

Environment

This problem appears to have been around for a while: nightly toolchains from 2023-07-10a up to 2024-04-11a exhibit this issue.
M1 MacBook; Xcode 15.1.

Additional information

The full stack trace is shown below:

1.      Apple Swift version 6.0-dev (LLVM 40c342d107dc66e, Swift 22919a9039e20a1)
2.      Compiling with effective version 5.10
3.      While evaluating request ExecuteSILPipelineRequest(Run pipelines { Mandatory Diagnostic Passes + Enabling Optimization Passes } on SIL for _0000)
4.      While running pass #466 SILModuleTransform "Differentiation".
5.      While processing // differentiability witness for A.i(x:v:)
sil_differentiability_witness [serialized] [reverse] [parameters 1 2] [results 0] <I, D where I : Hashable, D : Differentiable> @$s5_00001AV1i1x1vyx_18OrderedCollections0A10DictionaryVySSq_GtF : $@convention(method) <I, D where I : Hashable, D : Differentiable> (@in_guaranteed I, @guaranteed OrderedDictionary<String, D>, @inout A<I, D>) -> () {
}

 on SIL function "@$s5_00001AV1i1x1vyx_18OrderedCollections0A10DictionaryVySSq_GtF".
 for 'i(x:v:)' (at /Users/user/p/70000/Sources/main.swift:13:39)
6.      While generating VJP for SIL function "@$s5_00001AV1i1x1vyx_18OrderedCollections0A10DictionaryVySSq_GtF".
 for 'i(x:v:)' (at /Users/user/p/70000/Sources/main.swift:13:39)
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           0x00000001096d1098 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 56
1  swift-frontend           0x00000001096cf864 llvm::sys::RunSignalHandlers() + 112
2  swift-frontend           0x00000001096d16e0 SignalHandler(int) + 304
3  libsystem_platform.dylib 0x000000018b5d9a24 _sigtramp + 56
4  libsystem_pthread.dylib  0x000000018b5a9cc0 pthread_kill + 288
5  libsystem_c.dylib        0x000000018b4b5a40 abort + 180
6  libsystem_c.dylib        0x000000018b4b4d30 err + 0
7  swift-frontend           0x0000000109ba7da8 swift::Mangle::ASTMangler::appendAnyProtocolConformance(swift::GenericSignature, swift::CanType, swift::ProtocolConformanceRef) (.cold.6) + 0
8  swift-frontend           0x000000010586ae30 swift::Mangle::ASTMangler::appendAnyProtocolConformance(swift::GenericSignature, swift::CanType, swift::ProtocolConformanceRef) + 672
9  swift-frontend           0x0000000105865c5c swift::Mangle::ASTMangler::appendConcreteProtocolConformance(swift::ProtocolConformance const*, swift::GenericSignature) + 432
10 swift-frontend           0x000000010586572c swift::Mangle::ASTMangler::appendRetroactiveConformances(swift::SubstitutionMap, swift::GenericSignature) + 116
11 swift-frontend           0x00000001058622d8 swift::Mangle::ASTMangler::appendRetroactiveConformances(swift::Type, swift::GenericSignature) + 180
12 swift-frontend           0x000000010585cd14 swift::Mangle::ASTMangler::appendType(swift::Type, swift::GenericSignature, swift::ValueDecl const*) + 2716
13 swift-frontend           0x00000001058639c4 swift::Mangle::ASTMangler::appendImplFunctionType(swift::SILFunctionType*, swift::GenericSignature, swift::ValueDecl const*) + 2976
14 swift-frontend           0x000000010585e2cc swift::Mangle::ASTMangler::mangleReabstractionThunkHelper(swift::CanTypeWrapper<swift::SILFunctionType>, swift::Type, swift::Type, swift::Type, swift::Type, swift::ModuleDecl*) + 160
15 swift-frontend           0x0000000104a5f568 swift::autodiff::getOrCreateReabstractionThunk(swift::SILOptFunctionBuilder&, swift::SILModule&, swift::SILLocation, swift::SILFunction*, swift::CanTypeWrapper<swift::SILFunctionType>, swift::CanTypeWrapper<swift::SILFunctionType>) + 752
16 swift-frontend           0x0000000104a610b8 swift::autodiff::reabstractFunction(swift::SILBuilder&, swift::SILOptFunctionBuilder&, swift::SILLocation, swift::SILValue, swift::CanTypeWrapper<swift::SILFunctionType>, std::__1::function<swift::SubstitutionMap (swift::SubstitutionMap)>) + 188
17 swift-frontend           0x0000000104a70e60 swift::autodiff::VJPCloner::Implementation::visitApplyInst(swift::ApplyInst*) + 3420
18 swift-frontend           0x0000000104a6877c swift::SILCloner<swift::autodiff::VJPCloner::Implementation>::visitBlocksDepthFirst(swift::SILBasicBlock*) + 380
19 swift-frontend           0x0000000104a67bf4 swift::SILCloner<swift::autodiff::VJPCloner::Implementation>::cloneFunctionBody(swift::SILFunction*, swift::SILBasicBlock*, llvm::ArrayRef<swift::SILValue>, bool) + 236
20 swift-frontend           0x0000000104a673b4 swift::autodiff::VJPCloner::Implementation::run() + 920
21 swift-frontend           0x0000000104a67c54 swift::autodiff::VJPCloner::run() + 24
22 swift-frontend           0x0000000104bc1b88 (anonymous namespace)::DifferentiationTransformer::canonicalizeDifferentiabilityWitness(swift::SILDifferentiabilityWitness*, swift::autodiff::DifferentiationInvoker, swift::IsSerialized_t) + 6028
23 swift-frontend           0x0000000104bbfa0c (anonymous namespace)::Differentiation::run() + 1060
24 swift-frontend           0x0000000104c62ec4 swift::SILPassManager::runModulePass(unsigned int) + 856
25 swift-frontend           0x0000000104c65268 swift::SILPassManager::execute() + 624
26 swift-frontend           0x0000000104c5fc44 swift::SILPassManager::executePassPipelinePlan(swift::SILPassPipelinePlan const&) + 72
27 swift-frontend           0x0000000104c5fbc4 swift::ExecuteSILPipelineRequest::evaluate(swift::Evaluator&, swift::SILPipelineExecutionDescriptor) const + 68
28 swift-frontend           0x0000000104c9b2f4 swift::SimpleRequest<swift::ExecuteSILPipelineRequest, std::__1::tuple<> (swift::SILPipelineExecutionDescriptor), (swift::RequestFlags)1>::evaluateRequest(swift::ExecuteSILPipelineRequest const&, swift::Evaluator&) + 28
29 swift-frontend           0x0000000104c7b7dc swift::ExecuteSILPipelineRequest::OutputType swift::Evaluator::getResultUncached<swift::ExecuteSILPipelineRequest, swift::ExecuteSILPipelineRequest::OutputType swift::evaluateOrFatal<swift::ExecuteSILPipelineRequest>(swift::Evaluator&, swift::ExecuteSILPipelineRequest)::'lambda'()>(swift::ExecuteSILPipelineRequest const&, swift::ExecuteSILPipelineRequest::OutputType swift::evaluateOrFatal<swift::ExecuteSILPipelineRequest>(swift::Evaluator&, swift::ExecuteSILPipelineRequest)::'lambda'()) + 204
30 swift-frontend           0x0000000104c5fe20 swift::executePassPipelinePlan(swift::SILModule*, swift::SILPassPipelinePlan const&, bool, swift::irgen::IRGenModule*) + 64
31 swift-frontend           0x0000000104c7dcc0 swift::runSILDiagnosticPasses(swift::SILModule&) + 192
32 swift-frontend           0x00000001044c28ec swift::CompilerInstance::performSILProcessing(swift::SILModule*) + 68
33 swift-frontend           0x0000000104287968 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*) + 796
34 swift-frontend           0x000000010428707c swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 612
35 swift-frontend           0x00000001042982b4 withSemanticAnalysis(swift::CompilerInstance&, swift::FrontendObserver*, llvm::function_ref<bool (swift::CompilerInstance&)>, bool) + 160
36 swift-frontend           0x000000010428968c performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 708
37 swift-frontend           0x00000001042885f8 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 2368
38 swift-frontend           0x00000001040a4448 swift::mainEntry(int, char const**) + 3096
39 dyld                     0x000000018b2290e0 start + 2360

Note that this issue may be similar to others that already exist, for example, this one
#68689
Unlike 68689, however, this does not require a secondary internal Package.