class C {}
class C1 : Any, C {}

/Users/Hamish/Desktop/main.swift:10:17: error: superclass 'C' must appear first in the inheritance clause
class C1 : Any, C {}
              ~~^
           C,
0  swift                    0x0000000111fc8298 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 40
1  swift                    0x0000000111fc7507 llvm::sys::RunSignalHandlers() + 39
2  swift                    0x0000000111fc8912 SignalHandler(int) + 258
3  libsystem_platform.dylib 0x00007fff59804f5a _sigtramp + 26
4  libsystem_platform.dylib 0x0000000000000020 _sigtramp + 2793386208
5  swift                    0x000000010f528059 swift::TypeBase::getCanonicalType() const + 25
6  swift                    0x000000010f5377f5 swift::TypeBase::getAnyNominal() + 21
7  swift                    0x000000010edeab72 swift::AccessControlChecker::check(swift::Decl*)::$_11::operator()(swift::TypeLoc) const + 146
8  swift                    0x000000010edded4a swift::AccessControlChecker::check(swift::Decl*) + 3258
9  swift                    0x000000010eea69ed swift::AccessControlChecker::checkAccessControl(swift::TypeChecker&, swift::Decl*) + 45
10 swift                    0x000000010eea2a23 (anonymous namespace)::DeclChecker::visitClassDecl(swift::ClassDecl*) + 2979
11 swift                    0x000000010ee9feee swift::ASTVisitor<(anonymous namespace)::DeclChecker, void, void, void, void, void, void>::visit(swift::Decl*) + 302
12 swift                    0x000000010ee7de5f (anonymous namespace)::DeclChecker::visit(swift::Decl*) + 303
13 swift                    0x000000010ee7dcf9 swift::TypeChecker::typeCheckDecl(swift::Decl*) + 73
14 swift                    0x000000010f01d69a swift::performTypeChecking(swift::SourceFile&, swift::TopLevelContext&, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>, unsigned int, unsigned int, unsigned int, unsigned int, unsigned int) + 1274
15 swift                    0x000000010e5efc32 swift::CompilerInstance::parseAndTypeCheckMainFile(swift::PersistentParserState&, swift::DelayedParsingCallbacks*, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>) + 1010
16 swift                    0x000000010e5eb858 swift::CompilerInstance::parseAndCheckTypes(swift::CompilerInstance::ImplicitImports const&) + 776
17 swift                    0x000000010e5eaf9f swift::CompilerInstance::performSema() + 1903
18 swift                    0x000000010d2ed8f1 performCompile(swift::CompilerInstance&, swift::CompilerInvocation&, llvm::ArrayRef<char const*>, int&, swift::FrontendObserver*, swift::UnifiedStatsReporter*) + 369
19 swift                    0x000000010d2eb90c swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 5020
20 swift                    0x000000010d20e5c5 run_driver(llvm::StringRef, llvm::ArrayRef<char const*>) + 917
21 swift                    0x000000010d20ced1 main + 4721
22 libdyld.dylib            0x00007fff594f6015 start + 1
Stack dump:
0.  Program arguments: /Users/Hamish/Desktop/swift-dev/build/Ninja-RelWithDebInfoAssert+swift-DebugAssert/swift-macosx-x86_64/bin/swift -frontend -c -primary-file /Users/Hamish/Desktop/main.swift -target x86_64-apple-darwin17.6.0 -enable-objc-interop -color-diagnostics -module-name null -o /var/folders/2s/m9mqt6bx6bsbfzt64whnsf080000gp/T/main-560e65.o
1.  While type-checking 'C1' at /Users/Hamish/Desktop/main.swift:10:1
<unknown>:0: error: unable to execute command: Segmentation fault: 11