Sema: Remove unnecessary circularity breaks

include/swift/AST/TypeCheckRequests.h

@@ -1209,6 +1209,7 @@ class UnderlyingTypeRequest :
   bool isCached() const { return true; }
   Optional<Type> getCachedResult() const;
   void cacheResult(Type value) const;
+  void diagnoseCycle(DiagnosticEngine &diags) const;
 };
 
 class OperatorPrecedenceGroupRequest

lib/AST/ASTContext.cpp

@@ -3407,8 +3407,6 @@ ProtocolType::ProtocolType(ProtocolDecl *TheDecl, Type Parent,
   : NominalType(TypeKind::Protocol, &Ctx, TheDecl, Parent, properties) { }
 
 LValueType *LValueType::get(Type objectTy) {
-  assert(!objectTy->hasError() &&
-         "cannot have ErrorType wrapped inside LValueType");
   assert(!objectTy->is<LValueType>() && !objectTy->is<InOutType>() &&
          "cannot have 'inout' or @lvalue wrapped inside an @lvalue");
 

lib/AST/Builtins.cpp

@@ -162,7 +162,6 @@ getBuiltinFunction(Identifier Id, ArrayRef<Type> argTypes, Type ResType,
         ParamDecl(ParamDecl::Specifier::Default, SourceLoc(), SourceLoc(),
                   Identifier(), SourceLoc(), Identifier(), DC);
     PD->setInterfaceType(argType);
-    PD->setValidationToChecked();
     PD->setImplicit();
     params.push_back(PD);
   }
@@ -179,7 +178,6 @@ getBuiltinFunction(Identifier Id, ArrayRef<Type> argTypes, Type ResType,
                              paramList,
                              TypeLoc::withoutLoc(ResType), DC);
   FD->computeType(Info);
-  FD->setValidationToChecked();
   FD->setImplicit();
   FD->setAccess(AccessLevel::Public);
   return FD;
@@ -209,7 +207,6 @@ getBuiltinGenericFunction(Identifier Id,
                                       Identifier(), SourceLoc(),
                                       Identifier(), DC);
     PD->setInterfaceType(paramIfaceType);
-    PD->setValidationToChecked();
     PD->setImplicit();
     params.push_back(PD);
   }
@@ -228,7 +225,6 @@ getBuiltinGenericFunction(Identifier Id,
 
   func->setGenericSignature(Sig);
   func->computeType();
-  func->setValidationToChecked();
   func->setImplicit();
   func->setAccess(AccessLevel::Public);
 

lib/AST/Decl.cpp

@@ -1361,7 +1361,6 @@ ParamDecl *PatternBindingInitializer::getImplicitSelfDecl() {
                                     C.Id_self, this);
       SelfParam->setImplicit();
       SelfParam->setInterfaceType(DC->getSelfInterfaceType());
-      SelfParam->setValidationToChecked();
     }
   }
 
@@ -3864,7 +3863,6 @@ GetDestructorRequest::evaluate(Evaluator &evaluator, ClassDecl *CD) const {
   auto *DD = new (ctx) DestructorDecl(CD->getLoc(), CD);
 
   DD->setImplicit();
-  DD->setValidationToChecked();
 
   // Synthesize an empty body for the destructor as needed.
   DD->setBodySynthesizer(synthesizeEmptyFunctionBody);
@@ -6664,8 +6662,6 @@ void AbstractFunctionDecl::computeSelfDeclType() {
                        ? ParamDecl::Specifier::InOut
                        : ParamDecl::Specifier::Default;
   selfDecl->setSpecifier(specifier);
-
-  selfDecl->setValidationToChecked();
 }
 
 void AbstractFunctionDecl::setParameters(ParameterList *BodyParams) {

lib/AST/Module.cpp

@@ -103,7 +103,6 @@ void BuiltinUnit::LookupCache::lookupValue(
                                           const_cast<BuiltinUnit*>(&M));
       TAD->setUnderlyingType(Ty);
       TAD->setAccess(AccessLevel::Public);
-      TAD->setValidationToChecked();
       TAD->computeType();
       Entry = TAD;
     }
@@ -399,9 +398,6 @@ ModuleDecl::ModuleDecl(Identifier name, ASTContext &ctx)
   setImplicit();
   setInterfaceType(ModuleType::get(this));
 
-  // validateDecl() should return immediately given a ModuleDecl.
-  setValidationToChecked();
-
   setAccess(AccessLevel::Public);
 }
 

lib/AST/TypeCheckRequests.cpp

@@ -12,6 +12,7 @@
 #include "swift/AST/ASTContext.h"
 #include "swift/AST/Decl.h"
 #include "swift/AST/DiagnosticsCommon.h"
+#include "swift/AST/DiagnosticsSema.h"
 #include "swift/AST/Module.h"
 #include "swift/AST/NameLookup.h"
 #include "swift/AST/PropertyWrappers.h"
@@ -855,6 +856,13 @@ void UnderlyingTypeRequest::cacheResult(Type value) const {
   typeAlias->UnderlyingTy.setType(value);
 }
 
+void UnderlyingTypeRequest::diagnoseCycle(DiagnosticEngine &diags) const {
+  auto aliasDecl = std::get<0>(getStorage());
+  diags.diagnose(aliasDecl, diag::recursive_decl_reference,
+                 aliasDecl->getDescriptiveKind(),
+                 aliasDecl->getName());
+}
+
 //----------------------------------------------------------------------------//
 // EnumRawValuesRequest computation.
 //----------------------------------------------------------------------------//

lib/ClangImporter/ImportDecl.cpp

@@ -137,7 +137,6 @@ createVarWithPattern(ASTContext &ctx, DeclContext *dc, Identifier name, Type ty,
   if (isImplicit)
     var->setImplicit();
   var->setInterfaceType(ty);
-  var->setValidationToChecked();
   var->setAccess(access);
   var->setSetterAccess(setterAccess);
 
@@ -528,7 +527,6 @@ makeEnumRawValueConstructor(ClangImporter::Implementation &Impl,
                                  SourceLoc(), C.Id_rawValue,
                                  enumDecl);
   param->setInterfaceType(rawTy);
-  param->setValidationToChecked();
 
   auto paramPL = ParameterList::createWithoutLoc(param);
 
@@ -543,7 +541,6 @@ makeEnumRawValueConstructor(ClangImporter::Implementation &Impl,
   ctorDecl->setAccess(AccessLevel::Public);
 
   ctorDecl->computeType();
-  ctorDecl->setValidationToChecked();
   ctorDecl->setBodySynthesizer(synthesizeEnumRawValueConstructorBody, enumDecl);
   return ctorDecl;
 }
@@ -620,7 +617,6 @@ static void makeEnumRawValueGetter(ClangImporter::Implementation &Impl,
   getterDecl->setIsTransparent(false);
 
   getterDecl->computeType();
-  getterDecl->setValidationToChecked();
 
   getterDecl->setAccess(AccessLevel::Public);
   getterDecl->setBodySynthesizer(synthesizeEnumRawValueGetterBody, enumDecl);
@@ -702,7 +698,6 @@ static AccessorDecl *makeStructRawValueGetter(
   getterDecl->setIsTransparent(false);
 
   getterDecl->computeType();
-  getterDecl->setValidationToChecked();
 
   getterDecl->setAccess(AccessLevel::Public);
   getterDecl->setBodySynthesizer(synthesizeStructRawValueGetterBody, storedVar);
@@ -734,7 +729,6 @@ static AccessorDecl *makeFieldGetterDecl(ClangImporter::Implementation &Impl,
   getterDecl->setIsDynamic(false);
 
   getterDecl->computeType();
-  getterDecl->setValidationToChecked();
 
   return getterDecl;
 }
@@ -771,7 +765,6 @@ static AccessorDecl *makeFieldSetterDecl(ClangImporter::Implementation &Impl,
   setterDecl->setAccess(AccessLevel::Public);
 
   setterDecl->computeType();
-  setterDecl->setValidationToChecked();
 
   return setterDecl;
 }
@@ -1316,7 +1309,6 @@ createDefaultConstructor(ClangImporter::Implementation &Impl,
 
   // Set the constructor's type.
   constructor->computeType();
-  constructor->setValidationToChecked();
 
   constructor->setAccess(AccessLevel::Public);
 
@@ -1429,7 +1421,6 @@ createValueConstructor(ClangImporter::Implementation &Impl,
         ParamDecl(ParamDecl::Specifier::Default, SourceLoc(), SourceLoc(), argName,
                   SourceLoc(), var->getName(), structDecl);
     param->setInterfaceType(var->getInterfaceType());
-    param->setValidationToChecked();
     Impl.recordImplicitUnwrapForDecl(param, var->isImplicitlyUnwrappedOptional());
     valueParameters.push_back(param);
   }
@@ -1446,7 +1437,6 @@ createValueConstructor(ClangImporter::Implementation &Impl,
 
   // Set the constructor's type.
   constructor->computeType();
-  constructor->setValidationToChecked();
 
   constructor->setAccess(AccessLevel::Public);
 
@@ -1488,7 +1478,6 @@ static void addSynthesizedTypealias(NominalTypeDecl *nominal, Identifier name,
                                            nullptr, nominal);
   typealias->setUnderlyingType(underlyingType);
   typealias->setAccess(AccessLevel::Public);
-  typealias->setValidationToChecked();
   typealias->setImplicit();
   typealias->computeType();
 
@@ -1664,7 +1653,6 @@ static void makeStructRawValuedWithBridge(
   computedVar->setImplicit();
   computedVar->setAccess(AccessLevel::Public);
   computedVar->setSetterAccess(AccessLevel::Private);
-  computedVar->setValidationToChecked();
 
   // Create the getter for the computed value variable.
   auto computedVarGetter = makeStructRawValueGetter(
@@ -1727,7 +1715,6 @@ buildSubscriptGetterDecl(ClangImporter::Implementation &Impl,
 
   thunk->setGenericSignature(dc->getGenericSignatureOfContext());
   thunk->computeType();
-  thunk->setValidationToChecked();
 
   thunk->setAccess(getOverridableAccessLevel(dc));
 
@@ -1762,7 +1749,6 @@ buildSubscriptSetterDecl(ClangImporter::Implementation &Impl,
       new (C) ParamDecl(ParamDecl::Specifier::Default, SourceLoc(), SourceLoc(),
                         Identifier(), loc, valueIndex->get(0)->getName(), dc);
   paramVarDecl->setInterfaceType(elementInterfaceTy);
-  paramVarDecl->setValidationToChecked();
 
   auto valueIndicesPL = ParameterList::create(C, {paramVarDecl, index});
 
@@ -1782,7 +1768,6 @@ buildSubscriptSetterDecl(ClangImporter::Implementation &Impl,
                      setter->getClangNode());
   thunk->setGenericSignature(dc->getGenericSignatureOfContext());
   thunk->computeType();
-  thunk->setValidationToChecked();
 
   thunk->setAccess(getOverridableAccessLevel(dc));
 
@@ -1951,7 +1936,6 @@ static bool addErrorDomain(NominalTypeDecl *swiftDecl,
       /*IsStatic*/isStatic, VarDecl::Introducer::Var, /*IsCaptureList*/false,
       SourceLoc(), C.Id_errorDomain, swiftDecl);
   errorDomainPropertyDecl->setInterfaceType(stringTy);
-  errorDomainPropertyDecl->setValidationToChecked();
   errorDomainPropertyDecl->setAccess(AccessLevel::Public);
 
   auto *params = ParameterList::createEmpty(C);
@@ -1970,7 +1954,6 @@ static bool addErrorDomain(NominalTypeDecl *swiftDecl,
                      TypeLoc::withoutLoc(stringTy), swiftDecl);
   getterDecl->setStatic(isStatic);
   getterDecl->computeType();
-  getterDecl->setValidationToChecked();
   getterDecl->setIsObjC(false);
   getterDecl->setIsDynamic(false);
   getterDecl->setIsTransparent(false);
@@ -2561,7 +2544,6 @@ namespace {
                             /*genericparams*/nullptr, DC);
               typealias->setUnderlyingType(
                   underlying->getDeclaredInterfaceType());
-              typealias->setValidationToChecked();
               typealias->computeType();
 
               Impl.SpecialTypedefNames[Decl->getCanonicalDecl()] =
@@ -2582,7 +2564,6 @@ namespace {
                             /*genericparams*/nullptr, DC);
               typealias->setUnderlyingType(
                 Impl.SwiftContext.getAnyObjectType());
-              typealias->setValidationToChecked();
               typealias->computeType();
 
               Impl.SpecialTypedefNames[Decl->getCanonicalDecl()] =
@@ -2651,7 +2632,6 @@ namespace {
                                       Loc,
                                       /*genericparams*/nullptr, DC);
       Result->setUnderlyingType(SwiftType);
-      Result->setValidationToChecked();
       Result->computeType();
 
       // Make Objective-C's 'id' unavailable.
@@ -2805,7 +2785,6 @@ namespace {
           // Create the wrapper struct.
           errorWrapper = new (C) StructDecl(loc, name, loc, None, nullptr, dc);
           errorWrapper->computeType();
-          errorWrapper->setValidationToChecked();
           errorWrapper->setAddedImplicitInitializers();
           errorWrapper->setAccess(AccessLevel::Public);
           errorWrapper->getAttrs().add(
@@ -2840,7 +2819,6 @@ namespace {
           nsErrorProp->setImplicit();
           nsErrorProp->setAccess(AccessLevel::Public);
           nsErrorProp->setInterfaceType(nsErrorType);
-          nsErrorProp->setValidationToChecked();
 
           // Create a pattern binding to describe the variable.
           Pattern *nsErrorPattern = createTypedNamedPattern(nsErrorProp);
@@ -2918,7 +2896,6 @@ namespace {
         rawValue->setAccess(AccessLevel::Public);
         rawValue->setSetterAccess(AccessLevel::Private);
         rawValue->setInterfaceType(underlyingType);
-        rawValue->setValidationToChecked();
 
         // Create a pattern binding to describe the variable.
         Pattern *varPattern = createTypedNamedPattern(rawValue);
@@ -2947,7 +2924,6 @@ namespace {
                          C.Id_ErrorType, loc,
                          /*genericparams=*/nullptr, enumDecl);
           alias->setUnderlyingType(errorWrapper->getDeclaredInterfaceType());
-          alias->setValidationToChecked();
           alias->computeType();
           enumDecl->addMember(alias);
 
@@ -3775,7 +3751,6 @@ namespace {
       result->setIsObjC(false);
       result->setIsDynamic(false);
       result->computeType();
-      result->setValidationToChecked();
 
       Impl.recordImplicitUnwrapForDecl(result,
                                        importedType.isImplicitlyUnwrapped());
@@ -4033,7 +4008,6 @@ namespace {
           Loc,
           /*genericparams*/nullptr, DC);
       Result->setUnderlyingType(SwiftTypeDecl->getDeclaredInterfaceType());
-      Result->setValidationToChecked();
       Result->computeType();
 
       return Result;
@@ -4364,7 +4338,6 @@ namespace {
 
       // Compute the interface type.
       result->computeType();
-      result->setValidationToChecked();
 
       Impl.recordImplicitUnwrapForDecl(result, isIUO);
 
@@ -4572,7 +4545,6 @@ namespace {
       SmallVector<TypeLoc, 4> inheritedTypes;
       importObjCProtocols(result, decl->getReferencedProtocols(),
                           inheritedTypes);
-      result->setValidationToChecked();
       result->setInherited(Impl.SwiftContext.AllocateCopy(inheritedTypes));
       result->setMemberLoader(&Impl, 0);
 
@@ -5169,7 +5141,6 @@ namespace {
       }
 
       typealias->setUnderlyingType(typeDecl->getDeclaredInterfaceType());
-      typealias->setValidationToChecked();
       typealias->computeType();
       return typealias;
     }
@@ -5406,7 +5377,6 @@ Decl *SwiftDeclConverter::importCompatibilityTypeAlias(
   }
 
   alias->setUnderlyingType(typeDecl->getDeclaredInterfaceType());
-  alias->setValidationToChecked();
   alias->computeType();
 
   // Record that this is the official version of this declaration.
@@ -5816,7 +5786,6 @@ Decl *SwiftDeclConverter::importGlobalAsInitializer(
             ParamDecl::Specifier::Default, SourceLoc(), SourceLoc(), argNames.front(),
             SourceLoc(), argNames.front(), dc);
     paramDecl->setInterfaceType(Impl.SwiftContext.TheEmptyTupleType);
-    paramDecl->setValidationToChecked();
 
     parameterList = ParameterList::createWithoutLoc(paramDecl);
   } else {
@@ -8138,7 +8107,6 @@ ClangImporter::Implementation::importDeclContextOf(
                                      nominal->getDeclaredType());
   SwiftContext.evaluator.cacheOutput(ExtendedNominalRequest{ext},
                                      std::move(nominal));
-  ext->setValidationToChecked();
   ext->setMemberLoader(this, reinterpret_cast<uintptr_t>(declSubmodule));
 
   if (auto protoDecl = ext->getExtendedProtocolDecl()) {
@@ -8384,7 +8352,6 @@ ClangImporter::Implementation::createConstant(Identifier name, DeclContext *dc,
     var = new (SwiftContext)
         VarDecl(/*IsStatic*/isStatic, VarDecl::Introducer::Var,
                 /*IsCaptureList*/false, SourceLoc(), name, dc);
-    var->setValidationToChecked();
   }
 
   var->setInterfaceType(type);
@@ -8409,7 +8376,6 @@ ClangImporter::Implementation::createConstant(Identifier name, DeclContext *dc,
   func->setStatic(isStatic);
   func->computeType();
   func->setAccess(getOverridableAccessLevel(dc));
-  func->setValidationToChecked();
   func->setIsObjC(false);
   func->setIsDynamic(false);
 

lib/ClangImporter/ImporterImpl.h

@@ -1234,8 +1234,6 @@ class LLVM_LIBRARY_VISIBILITY ClangImporter::Implementation
     D->setAccess(access);
     if (auto ASD = dyn_cast<AbstractStorageDecl>(D))
       ASD->setSetterAccess(access);
-    // All imported decls are constructed fully validated.
-    D->setValidationToChecked();
     if (auto AFD = dyn_cast<AbstractFunctionDecl>(static_cast<Decl *>(D)))
       AFD->setNeedsNewVTableEntry(false);
     return D;