XCode 11.1 reliably segmentation fault 11 in compile

When building I am seeing reliable segmentation fault 11 errors on one project. If I refactor the code into smaller parts it some times gets that one part to compile but then another fails. The current failure is in a 3 line function I can not really refactor further. Any suggestions on workarounds welcome.

struct Project : Codable, Identifiable, Equatable, ListEntry {
  var id : UUID = UUID()
  var name : String = UUID().uuidString
  
  func save(store: UndoableEventStore, n: Int) {
    let act = ListAction.create(at: n, obj:self)
    let e = ListChange<Project,Role>(subject: self.id,
      action: act)
    store.append(e)
  }
}

1. While emitting IR SIL function "@$s4Ladi7ProjectV4save5store1nyAA18UndoableEventStoreC_SitF".

for 'save(store:n:)' (at /Users/lattam/Projects/Ladi/Ladi/Models/Project.swift:17:3)

0 swift 0x0000000104d87a13 PrintStackTraceSignalHandler(void*) + 51

1 swift 0x0000000104d871e6 SignalHandler(int) + 358

2 libsystem_platform.dylib 0x00007fff6b6dab1d _sigtramp + 29

3 libsystem_platform.dylib 0x00000001063dbe00 _sigtramp + 2597327616

4 swift 0x0000000100c5b615 emitDirectTypeMetadataRef(swift::irgen::IRGenFunction&, swift::CanType, swift::irgen::DynamicMetadataRequest) + 197

5 swift 0x0000000100c5ff05 swift::irgen::IRGenFunction::emitTypeMetadataRef(swift::CanType, swift::irgen::DynamicMetadataRequest) + 149

6 swift 0x0000000100c61670 swift::CanTypeVisitor<(anonymous namespace)::EmitTypeMetadataRefForLayout, llvm::Value*, swift::irgen::DynamicMetadataRequest>::visit(swift::CanType, swift::irgen::DynamicMetadataRequest) + 112

7 swift 0x0000000100c61bea swift::CanTypeVisitor<(anonymous namespace)::EmitTypeMetadataRefForLayout, llvm::Value*, swift::irgen::DynamicMetadataRequest>::visit(swift::CanType, swift::irgen::DynamicMetadataRequest) + 1514

8 swift 0x0000000100c61fbc swift::irgen::IRGenFunction::emitTypeMetadataRefForLayout(swift::SILType, swift::irgen::DynamicMetadataRequest) + 44

9 swift 0x0000000100b78253 swift::irgen::IRGenFunction::emitValueWitnessTableRef(swift::SILType, swift::irgen::DynamicMetadataRequest, llvm::Value**) + 211

10 swift 0x0000000100b87b68 swift::irgen::emitLoadOfSize(swift::irgen::IRGenFunction&, swift::SILType) + 168

11 swift 0x0000000100ada82d swift::irgen::WitnessSizedTypeInfo<(anonymous namespace)::NonFixedEnumTypeInfo>::allocateStack(swift::irgen::IRGenFunction&, swift::SILType, llvm::Twine const&) const + 45

12 swift 0x0000000100c16758 swift::SILInstructionVisitor<(anonymous namespace)::IRGenSILFunction, void>::visit(swift::SILInstruction*) + 37608

13 swift 0x0000000100c0a8fa swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 9834

14 swift 0x0000000100ab7080 swift::irgen::IRGenerator::emitGlobalTopLevel() + 1712

15 swift 0x0000000100be7675 performIRGeneration(swift::IRGenOptions&, swift::ModuleDecl*, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule> >, llvm::StringRef, swift::PrimarySpecificPaths const&, llvm::LLVMContext&, swift::SourceFile*, llvm::GlobalVariable**) + 1189

16 swift 0x00000001009d3e31 performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&, swift::FrontendObserver*, swift::UnifiedStatsReporter*) + 36673

17 swift 0x00000001009c76e4 swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 6820

18 swift 0x0000000100954be3 main + 1219

19 libdyld.dylib 0x00007fff6b4d92e5 start + 1

error: Segmentation fault: 11 (in target 'Ladi' from project 'Ladi')