Merge pull request #24912 from slavapestov/drop-inherited-clause-entries

Serialization: Recover from failure to deserialize inheritance clause entries

Author: slavapestov

lib/Serialization/Deserialization.cpp

@@ -2301,13 +2301,23 @@ class swift::DeclDeserializer {
     AttrsNext = Attr->getMutableNext();
   };
 
-  void handleInherited(TypeDecl *nominal, ArrayRef<uint64_t> rawInheritedIDs) {
-    auto inheritedTypes = ctx.Allocate<TypeLoc>(rawInheritedIDs.size());
-    for_each(inheritedTypes, rawInheritedIDs,
-             [this](TypeLoc &tl, uint64_t rawID) {
-       tl = TypeLoc::withoutLoc(MF.getType(rawID));
-    });
-    nominal->setInherited(inheritedTypes);
+  void handleInherited(llvm::PointerUnion<TypeDecl *, ExtensionDecl *> decl,
+                       ArrayRef<uint64_t> rawInheritedIDs) {
+    SmallVector<TypeLoc, 2> inheritedTypes;
+    for (auto rawID : rawInheritedIDs) {
+      auto maybeType = MF.getTypeChecked(rawID);
+      if (!maybeType) {
+        llvm::consumeError(maybeType.takeError());
+        continue;
+      }
+      inheritedTypes.push_back(TypeLoc::withoutLoc(MF.getType(rawID)));
+    }
+
+    auto inherited = ctx.AllocateCopy(inheritedTypes);
+    if (auto *typeDecl = decl.dyn_cast<TypeDecl *>())
+      typeDecl->setInherited(inherited);
+    else
+      decl.get<ExtensionDecl *>()->setInherited(inherited);
   }
 
 public:
@@ -3507,13 +3517,13 @@ class swift::DeclDeserializer {
     GenericEnvironmentID genericEnvID;
     TypeID rawTypeID;
     uint8_t rawAccessLevel;
-    unsigned numConformances, numInheritedTypes;
+    unsigned numConformances, numInherited;
     ArrayRef<uint64_t> rawInheritedAndDependencyIDs;
 
     decls_block::EnumLayout::readRecord(scratch, nameID, contextID,
                                         isImplicit, isObjC, genericEnvID,
                                         rawTypeID, rawAccessLevel,
-                                        numConformances, numInheritedTypes,
+                                        numConformances, numInherited,
                                         rawInheritedAndDependencyIDs);
 
     auto DC = MF.getDeclContext(contextID);
@@ -3522,7 +3532,7 @@ class swift::DeclDeserializer {
 
     Identifier name = MF.getIdentifier(nameID);
     for (TypeID dependencyID :
-           rawInheritedAndDependencyIDs.slice(numInheritedTypes)) {
+           rawInheritedAndDependencyIDs.slice(numInherited)) {
       auto dependency = MF.getTypeChecked(dependencyID);
       if (!dependency) {
         return llvm::make_error<TypeError>(
@@ -3557,8 +3567,8 @@ class swift::DeclDeserializer {
 
     theEnum->computeType();
 
-    handleInherited(theEnum,
-                    rawInheritedAndDependencyIDs.slice(0, numInheritedTypes));
+    auto rawInheritedIDs = rawInheritedAndDependencyIDs.slice(0, numInherited);
+    handleInherited(theEnum, rawInheritedIDs);
 
     theEnum->setMemberLoader(&MF, MF.DeclTypeCursor.GetCurrentBitNo());
     skipRecord(MF.DeclTypeCursor, decls_block::MEMBERS);
@@ -3816,12 +3826,8 @@ class swift::DeclDeserializer {
     if (isImplicit)
       extension->setImplicit();
 
-    auto inheritedTypes = ctx.Allocate<TypeLoc>(numInherited);
-    for_each(inheritedTypes, inheritedAndDependencyIDs.slice(0, numInherited),
-             [this](TypeLoc &tl, uint64_t rawID) {
-      tl = TypeLoc::withoutLoc(MF.getType(rawID));
-    });
-    extension->setInherited(inheritedTypes);
+    auto rawInheritedIDs = inheritedAndDependencyIDs.slice(0, numInherited);
+    handleInherited(extension, rawInheritedIDs);
 
     extension->setMemberLoader(&MF, MF.DeclTypeCursor.GetCurrentBitNo());
     skipRecord(MF.DeclTypeCursor, decls_block::MEMBERS);

test/Serialization/Recovery/private-conformances.swift

@@ -0,0 +1,60 @@
+// RUN: %empty-directory(%t)
+
+// Build the protocol library and conforming library to include PrivateProtocol.
+// RUN: %target-swift-frontend -emit-module -DPROTOCOL_LIB -DBEFORE %s -module-name protocol_lib -emit-module-path %t/protocol_lib.swiftmodule
+// RUN: %target-swift-frontend -emit-module -DCONFORMS_LIB %s -module-name conforms_lib -emit-module-path %t/conforms_lib.swiftmodule -I %t
+// RUN: %target-swift-frontend -emit-module -DINHERITS_LIB %s -module-name inherits_lib -emit-module-path %t/inherits_lib.swiftmodule -I %t
+
+// Rebuild the protocol library to omit PrivateProtocol.
+// RUN: %target-swift-frontend -emit-module -DPROTOCOL_LIB -DAFTER %s -module-name protocol_lib -emit-module-path %t/protocol_lib.swiftmodule
+
+// The conforming library's types should still deserialize.
+// RUN: %target-swift-ide-test -print-module -source-filename %s -D CONFORMS_LIB -module-to-print conforms_lib -I %t | %FileCheck %s
+
+// Make sure we *cannot* recover from a missing inherited protocol.
+// RUN: not --crash %target-swift-ide-test -print-module -source-filename %s -D INHERITS_LIB -module-to-print inherits_lib -I %t
+
+#if PROTOCOL_LIB
+
+#if BEFORE
+public protocol PrivateProtocol {}
+#endif
+
+#elseif CONFORMS_LIB
+import protocol_lib
+
+public protocol PublicProtocol {}
+
+// CHECK: class C1 : PublicProtocol {
+public class C1 : PrivateProtocol, PublicProtocol {}
+
+// CHECK: class C2 {
+public class C2 {}
+
+// CHECK: extension C2 : PublicProtocol {
+extension C2 : PrivateProtocol, PublicProtocol {}
+
+// CHECK: enum E1 : PublicProtocol {
+public enum E1 : PrivateProtocol, PublicProtocol {}
+
+// CHECK: enum E2 {
+public enum E2 {}
+
+// CHECK: extension E2 : PublicProtocol {
+extension E2 : PrivateProtocol, PublicProtocol {}
+
+// CHECK: struct S1 : PublicProtocol {
+public struct S1 : PrivateProtocol, PublicProtocol {}
+
+// CHECK: struct S2 {
+public struct S2 {}
+
+// CHECK: extension S2 : PublicProtocol {
+extension S2 : PrivateProtocol, PublicProtocol {}
+
+#elseif INHERITS_LIB
+import protocol_lib
+
+public protocol InheritsPrivateProtocol : PrivateProtocol {}
+
+#endif