C++ support for Objective-C lightweight generics.

Teach C++'s tentative parsing to handle specializations of Objective-C
class types (e.g., NSArray<NSString *>) as well as Objective-C
protocol qualifiers (id<NSCopying>) by extending type-annotation
tokens to handle this case. As part of this, remove Objective-C
protocol qualifiers from the declaration specifiers, which never
really made sense: instead, provide Sema entry points to make them
part of the type annotation token. Among other things, this properly
diagnoses bogus types such as "<NSCopying> id" which should have been
written as "id <NSCopying>".

Implements template instantiation support for, e.g., NSArray<T>*
in C++. Note that parameterized classes are not templates in the C++
sense, so that cannot (for example) be used as a template argument for
a template template parameter. Part of rdar://problem/6294649.

llvm-svn: 241545

1 files changed, 24 insertions, 16 deletions

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 231f6d4d97a..9c12abab39d 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2144,8 +2144,7 @@ void Parser::ParseSpecifierQualifierList(DeclSpec &DS, AccessSpecifier AS,
   if (isTypeSpecifier(DSC) && !DS.hasTypeSpecifier()) {
     Diag(Tok, diag::err_expected_type);
     DS.SetTypeSpecError();
-  } else if (Specs == DeclSpec::PQ_None && !DS.getNumProtocolQualifiers() &&
-             !DS.hasAttributes()) {
+  } else if (Specs == DeclSpec::PQ_None && !DS.hasAttributes()) {
     Diag(Tok, diag::err_typename_requires_specqual);
     if (!DS.hasTypeSpecifier())
       DS.SetTypeSpecError();
@@ -2886,13 +2885,6 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       DS.SetRangeEnd(Tok.getAnnotationEndLoc());
       ConsumeToken(); // The typename
 
-      // Objective-C supports type arguments and protocol references
-      // following an Objective-C object pointer type. Handle either
-      // one of them.
-      if (Tok.is(tok::less) && getLangOpts().ObjC1) {
-        ParseObjCTypeArgsAndProtocolQualifiers(DS);
-      }
-
       continue;
     }
 
@@ -2999,10 +2991,17 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       ConsumeToken(); // The identifier
 
       // Objective-C supports type arguments and protocol references
-      // following an Objective-C object pointer type. Handle either
-      // one of them.
+      // following an Objective-C object or object pointer
+      // type. Handle either one of them.
       if (Tok.is(tok::less) && getLangOpts().ObjC1) {
-        ParseObjCTypeArgsAndProtocolQualifiers(DS);
+        SourceLocation NewEndLoc;
+        TypeResult NewTypeRep = parseObjCTypeArgsAndProtocolQualifiers(
+                                  Loc, TypeRep, /*consumeLastToken=*/true,
+                                  NewEndLoc);
+        if (NewTypeRep.isUsable()) {
+          DS.UpdateTypeRep(NewTypeRep.get());
+          DS.SetRangeEnd(NewEndLoc);
+        }
       }
 
       // Need to support trailing type qualifiers (e.g. "id<p> const").
@@ -3420,10 +3419,19 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       if (DS.hasTypeSpecifier() || !getLangOpts().ObjC1)
         goto DoneWithDeclSpec;
 
-      if (!ParseObjCProtocolQualifiers(DS))
-        Diag(Loc, diag::warn_objc_protocol_qualifier_missing_id)
-          << FixItHint::CreateInsertion(Loc, "id")
-          << SourceRange(Loc, DS.getSourceRange().getEnd());
+      SourceLocation StartLoc = Tok.getLocation();
+      SourceLocation EndLoc;
+      TypeResult Type = parseObjCProtocolQualifierType(EndLoc);
+      if (Type.isUsable()) {
+        if (DS.SetTypeSpecType(DeclSpec::TST_typename, StartLoc, StartLoc,
+                               PrevSpec, DiagID, Type.get(),
+                               Actions.getASTContext().getPrintingPolicy()))
+          Diag(StartLoc, DiagID) << PrevSpec;
+        
+        DS.SetRangeEnd(EndLoc);
+      } else {
+        DS.SetTypeSpecError();
+      }
 
       // Need to support trailing type qualifiers (e.g. "id<p> const").
       // If a type specifier follows, it will be diagnosed elsewhere.