swift234

[swiftc] Add test case for crash triggered in swift::ValueDecl::getInterfaceType() const

Stack trace:

```
4  swift           0x000000000103cc7c swift::ValueDecl::getInterfaceType() const + 12
5  swift           0x000000000103d836 swift::TypeDecl::getDeclaredInterfaceType() const + 6
6  swift           0x0000000000e7b8a1 swift::DependentGenericTypeResolver::resolveTypeOfContext(swift::DeclContext*) + 81
7  swift           0x0000000000ea979f swift::TypeChecker::resolveTypeInContext(swift::TypeDecl*, swift::DeclContext*, swift::OptionSet<swift::TypeResolutionFlags, unsigned int>, bool, swift::GenericTypeResolver*, llvm::function_ref<bool (swift::TypeCheckRequest)>*) + 911
11 swift           0x0000000000eaaa1e swift::TypeChecker::resolveIdentifierType(swift::DeclContext*, swift::IdentTypeRepr*, swift::OptionSet<swift::TypeResolutionFlags, unsigned int>, bool, swift::GenericTypeResolver*, llvm::function_ref<bool (swift::TypeCheckRequest)>*) + 158
13 swift           0x0000000000eab934 swift::TypeChecker::resolveType(swift::TypeRepr*, swift::DeclContext*, swift::OptionSet<swift::TypeResolutionFlags, unsigned int>, swift::GenericTypeResolver*, llvm::function_ref<bool (swift::TypeCheckRequest)>*) + 164
14 swift           0x0000000000eaa91a swift::TypeChecker::validateType(swift::TypeLoc&, swift::DeclContext*, swift::OptionSet<swift::TypeResolutionFlags, unsigned int>, swift::GenericTypeResolver*, llvm::function_ref<bool (swift::TypeCheckRequest)>*) + 42
15 swift           0x0000000000e7c162 swift::TypeChecker::checkGenericParamList(swift::ArchetypeBuilder*, swift::GenericParamList*, swift::GenericSignature*, bool, swift::GenericTypeResolver*) + 690
16 swift           0x0000000000e7d737 swift::TypeChecker::validateGenericSignature(swift::GenericParamList*, swift::DeclContext*, swift::GenericSignature*, std::function<bool (swift::ArchetypeBuilder&)>, bool&) + 135
17 swift           0x0000000000e7dad6 swift::TypeChecker::validateGenericTypeSignature(swift::GenericTypeDecl*) + 102
18 swift           0x0000000000e40b42 swift::TypeChecker::validateDecl(swift::ValueDecl*, bool) + 1554
23 swift           0x0000000000e46196 swift::TypeChecker::typeCheckDecl(swift::Decl*, bool) + 150
26 swift           0x0000000000ea59ba swift::TypeChecker::typeCheckClosureBody(swift::ClosureExpr*) + 218
27 swift           0x0000000000ed14ac swift::constraints::ConstraintSystem::applySolution(swift::constraints::Solution&, swift::Expr*, swift::Type, bool, bool, bool) + 812
28 swift           0x0000000000e33eca swift::TypeChecker::typeCheckExpression(swift::Expr*&, swift::DeclContext*, swift::Type, swift::ContextualTypePurpose, swift::OptionSet<swift::TypeCheckExprFlags, unsigned int>, swift::ExprTypeCheckListener*) + 746
30 swift           0x0000000000ea5b06 swift::TypeChecker::typeCheckTopLevelCodeDecl(swift::TopLevelCodeDecl*) + 134
31 swift           0x0000000000e6958d swift::performTypeChecking(swift::SourceFile&, swift::TopLevelContext&, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>, unsigned int) + 1149
32 swift           0x0000000000cbc58f swift::CompilerInstance::performSema() + 3087
34 swift           0x000000000078b54f frontend_main(llvm::ArrayRef<char const*>, char const*, void*) + 2495
35 swift           0x0000000000786015 main + 2837
Stack dump:
0.	Program arguments: /path/to/swift/bin/swift -frontend -c -primary-file validation-test/compiler_crashers/28264-swift-valuedecl-getinterfacetype.swift -target x86_64-unknown-linux-gnu -disable-objc-interop -module-name main -o /tmp/28264-swift-valuedecl-getinterfacetype-d01804.o
1.	While type-checking expression at [validation-test/compiler_crashers/28264-swift-valuedecl-getinterfacetype.swift:9:1 - line:9:35] RangeText="{class A{typealias B<T where B:T>:v"
2.	While type-checking 'A' at validation-test/compiler_crashers/28264-swift-valuedecl-getinterfacetype.swift:9:2
3.	While resolving type B at [validation-test/compiler_crashers/28264-swift-valuedecl-getinterfacetype.swift:9:30 - line:9:30] RangeText="B"
<unknown>:0: error: unable to execute command: Segmentation fault
<unknown>:0: error: compile command failed due to signal (use -v to see invocation)
```