[Modules][ObjC] ASTReader should add protocols for class extensions

During deserialization clang is currently missing the merging of
protocols into the canonical interface for the class extension.

This merging only currently happens during parsing and should also
be considered during deserialization.

rdar://problem/38724303

llvm-svn: 331063

clang/lib/Serialization/ASTReaderDecl.cpp

@@ -1205,6 +1205,12 @@ void ASTDeclReader::VisitObjCCategoryDecl(ObjCCategoryDecl *CD) {
     ProtoLocs.push_back(ReadSourceLocation());
   CD->setProtocolList(ProtoRefs.data(), NumProtoRefs, ProtoLocs.data(),
                       Reader.getContext());
+
+  // Protocols in the class extension belong to the class.
+  if (NumProtoRefs > 0 && CD->ClassInterface && CD->IsClassExtension())
+    CD->ClassInterface->mergeClassExtensionProtocolList(
+        (ObjCProtocolDecl *const *)ProtoRefs.data(), NumProtoRefs,
+        Reader.getContext());
 }
 
 void ASTDeclReader::VisitObjCCompatibleAliasDecl(ObjCCompatibleAliasDecl *CAD) {

clang/test/Modules/Inputs/class-extension/a-private.h

@@ -0,0 +1,5 @@
+#import "a.h"
+#import "a-proto.h"
+
+@interface A () <AProto>
+@end

clang/test/Modules/Inputs/class-extension/a-proto.h

@@ -0,0 +1,7 @@
+@protocol NSObject
+@end
+
+@protocol AProto <NSObject>
+@property (nonatomic, readwrite, assign) int p0;
+@property (nonatomic, readwrite, assign) int p1;
+@end

clang/test/Modules/Inputs/class-extension/a.h

@@ -0,0 +1,5 @@
+@interface NSObject
+@end
+
+@interface A : NSObject
+@end

clang/test/Modules/Inputs/class-extension/module.modulemap

@@ -0,0 +1,11 @@
+
+module A {
+  header "a.h"
+  header "a-proto.h"
+  export *
+}
+
+module AP {
+  header "a-private.h"
+  export *
+}

clang/test/Modules/class-extension-protocol.m

@@ -0,0 +1,9 @@
+// RUN: rm -rf %t.cache
+// RUN: %clang_cc1 %s -fsyntax-only -fmodules -fimplicit-module-maps -fmodules-cache-path=%t.cache -I%S/Inputs/class-extension -verify
+// expected-no-diagnostics
+
+#import "a-private.h"
+
+int foo(A *X) {
+  return X.p0 + X.p1;
+}