Merge pull request swiftlang#8936 from DougGregor/multi-file-conformance

Author: swift-ci

lib/Sema/TypeCheckAttr.cpp

@@ -1630,7 +1630,7 @@ void AttributeChecker::visitSpecializeAttr(SpecializeAttr *attr) {
 
   // Form a new generic signature based on the old one.
   GenericSignatureBuilder Builder(D->getASTContext(),
-                           LookUpConformanceInModule(DC->getParentModule()));
+                                  TypeChecker::LookUpConformance(TC, DC));
 
   // First, add the old generic signature.
   Builder.addGenericSignature(genericSig);

lib/Sema/TypeCheckGeneric.cpp

@@ -797,8 +797,7 @@ TypeChecker::validateGenericFuncSignature(AbstractFunctionDecl *func) {
   addGenericParamTypes(gp, allGenericParams);
 
   // Create the generic signature builder.
-  GenericSignatureBuilder builder(Context,
-                           LookUpConformanceInModule(func->getParentModule()));
+  GenericSignatureBuilder builder(Context, LookUpConformance(*this, func));
 
   // Type check the function declaration, treating all generic type
   // parameters as dependent, unresolved.
@@ -1028,8 +1027,7 @@ TypeChecker::validateGenericSubscriptSignature(SubscriptDecl *subscript) {
   addGenericParamTypes(gp, allGenericParams);
 
   // Create the generic signature builder.
-  GenericSignatureBuilder builder(Context,
-                       LookUpConformanceInModule(subscript->getParentModule()));
+  GenericSignatureBuilder builder(Context, LookUpConformance(*this, subscript));
 
   // Type check the function declaration, treating all generic type
   // parameters as dependent, unresolved.
@@ -1148,7 +1146,7 @@ GenericEnvironment *TypeChecker::checkGenericEnvironment(
 
   // Create the generic signature builder.
   ModuleDecl *module = dc->getParentModule();
-  GenericSignatureBuilder builder(Context, LookUpConformanceInModule(module));
+  GenericSignatureBuilder builder(Context, LookUpConformance(*this, dc));
 
   // Type check the generic parameters, treating all generic type
   // parameters as dependent, unresolved.

lib/Sema/TypeCheckProtocol.cpp

@@ -1017,12 +1017,13 @@ RequirementEnvironment::RequirementEnvironment(
   auto selfType = cast<GenericTypeParamType>(
                             proto->getSelfInterfaceType()->getCanonicalType());
 
-  // Construct a generic signature builder by collecting the constraints from the
-  // requirement and the context of the conformance together, because both
-  // define the capabilities of the requirement.
+  // Construct a generic signature builder by collecting the constraints
+  // from the requirement and the context of the conformance together,
+  // because both define the capabilities of the requirement.
   GenericSignatureBuilder builder(
            ctx,
-           LookUpConformanceInModule(conformanceDC->getParentModule()));
+           TypeChecker::LookUpConformance(tc, conformanceDC));
+
   SmallVector<GenericTypeParamType*, 4> allGenericParams;
 
   // Add the generic signature of the context of the conformance. This includes
@@ -4836,8 +4837,7 @@ void ConformanceChecker::ensureRequirementsAreSatisfied() {
       // FIXME: maybe this should be the conformance's type
       proto->getDeclaredInterfaceType(), reqSig,
       QuerySubstitutionMap{substitutions},
-      LookUpConformanceInModule(
-        Conformance->getDeclContext()->getParentModule()),
+      TypeChecker::LookUpConformance(TC, Conformance->getDeclContext()),
       nullptr,
       ConformanceCheckFlags::Used, &listener);
 
@@ -5328,6 +5328,21 @@ TypeChecker::conformsToProtocol(Type T, ProtocolDecl *Proto, DeclContext *DC,
                      : ConformsToProtocolResult::failure();
 }
 
+Optional<ProtocolConformanceRef>
+TypeChecker::LookUpConformance::operator()(
+                                       CanType dependentType,
+                                       Type conformingReplacementType,
+                                       ProtocolType *conformedProtocol) const {
+  if (conformingReplacementType->isTypeParameter())
+    return ProtocolConformanceRef(conformedProtocol->getDecl());
+
+  return tc.conformsToProtocol(conformingReplacementType,
+                               conformedProtocol->getDecl(),
+                               dc,
+                               (ConformanceCheckFlags::Used|
+                                ConformanceCheckFlags::InExpression));
+}
+
 /// Mark any _ObjectiveCBridgeable conformances in the given type as "used".
 ///
 /// These conformances might not appear in any substitution lists produced

lib/Sema/TypeCheckType.cpp

@@ -742,7 +742,7 @@ Type TypeChecker::applyUnboundGenericArguments(
     auto result =
       checkGenericArguments(dc, loc, noteLoc, unboundType, genericSig,
                             QueryTypeSubstitutionMap{subs},
-                            LookUpConformanceInModule{dc->getParentModule()},
+                            LookUpConformance(*this, dc),
                             unsatisfiedDependency);
 
     switch (result) {
@@ -757,7 +757,7 @@ Type TypeChecker::applyUnboundGenericArguments(
 
   // Apply the substitution map to the interface type of the declaration.
   resultType = resultType.subst(QueryTypeSubstitutionMap{subs},
-                                LookUpConformanceInModule(dc->getParentModule()),
+                                LookUpConformance(*this, dc),
                                 SubstFlags::UseErrorType);
 
   if (isa<NominalTypeDecl>(decl)) {

lib/Sema/TypeChecker.h

@@ -1819,6 +1819,23 @@ class TypeChecker final : public LazyResolver {
                      ConformanceCheckOptions options, SourceLoc ComplainLoc,
                      UnsatisfiedDependency *unsatisfiedDependency);
 
+  /// Functor class suitable for use as a \c LookupConformanceFn to look up a
+  /// conformance through a particular declaration context using the given
+  /// type checker.
+  class LookUpConformance {
+    TypeChecker &tc;
+    DeclContext *dc;
+
+  public:
+    explicit LookUpConformance(TypeChecker &tc, DeclContext *dc)
+      : tc(tc), dc(dc) { }
+
+    Optional<ProtocolConformanceRef>
+    operator()(CanType dependentType,
+               Type conformingReplacementType,
+               ProtocolType *conformedProtocol) const;
+  };
+
   /// Completely check the given conformance.
   void checkConformance(NormalProtocolConformance *conformance);
 

test/multifile/Inputs/for_each_conformance_crashB.swift

@@ -0,0 +1,12 @@
+protocol _P { }
+protocol P : _P { }
+
+protocol Q {
+  associatedtype A: P
+
+  func getArray() -> [RequiresP<A>]
+}
+
+struct RequiresP<T: P> { }
+
+struct MyStruct: P { }

test/multifile/for_each_conformance_crash.swift

@@ -0,0 +1,7 @@
+// RUN: %target-swift-frontend -emit-ir %S/Inputs/for_each_conformance_crashB.swift -primary-file %s -o -
+
+extension Q where A == MyStruct {
+  func foo() {
+    for _ in getArray() { }
+  }
+}