Make it possible for using decls to point to operators. Fixes PR4441.

llvm-svn: 74362

clang/include/clang/Parse/Action.h

@@ -967,12 +967,13 @@ public:
 
   /// ActOnUsingDirective - This is called when using-directive is parsed.
   virtual DeclPtrTy ActOnUsingDeclaration(Scope *CurScope,
-                                        SourceLocation UsingLoc,
-                                        const CXXScopeSpec &SS,
-                                        SourceLocation IdentLoc,
-                                        IdentifierInfo *TargetName,
-                                        AttributeList *AttrList,
-                                        bool IsTypeName);
+                                          SourceLocation UsingLoc,
+                                          const CXXScopeSpec &SS,
+                                          SourceLocation IdentLoc,
+                                          IdentifierInfo *TargetName,
+                                          OverloadedOperatorKind Op,
+                                          AttributeList *AttrList,
+                                          bool IsTypeName);
                                          
   /// ActOnParamDefaultArgument - Parse default argument for function parameter
   virtual void ActOnParamDefaultArgument(DeclPtrTy param,

clang/lib/Parse/MinimalAction.cpp

@@ -48,6 +48,7 @@ Action::DeclPtrTy Action::ActOnUsingDeclaration(Scope *CurScope,
                                               const CXXScopeSpec &SS,
                                               SourceLocation IdentLoc,
                                               IdentifierInfo *TargetName,
+                                              OverloadedOperatorKind Op,
                                               AttributeList *AttrList,
                                               bool IsTypeName) {
   

clang/lib/Parse/ParseDeclCXX.cpp

@@ -11,6 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Basic/OperatorKinds.h"
 #include "clang/Parse/Parser.h"
 #include "clang/Parse/ParseDiagnostic.h"
 #include "clang/Parse/DeclSpec.h"
@@ -274,8 +275,6 @@ Parser::DeclPtrTy Parser::ParseUsingDeclaration(unsigned Context,
   ParseOptionalCXXScopeSpecifier(SS);
 
   AttributeList *AttrList = 0;
-  IdentifierInfo *TargetName = 0;
-  SourceLocation IdentLoc = SourceLocation();
 
   // Check nested-name specifier.
   if (SS.isInvalid()) {
@@ -287,17 +286,33 @@ Parser::DeclPtrTy Parser::ParseUsingDeclaration(unsigned Context,
     SkipUntil(tok::semi);
     return DeclPtrTy();
   }
-  if (Tok.isNot(tok::identifier)) {
+  
+  IdentifierInfo *TargetName = 0;
+  OverloadedOperatorKind Op = OO_None;
+  SourceLocation IdentLoc;
+  
+  if (Tok.is(tok::kw_operator)) {
+    IdentLoc = Tok.getLocation();
+
+    Op = TryParseOperatorFunctionId();
+    if (!Op) {
+      // If there was an invalid operator, skip to end of decl, and eat ';'.
+      SkipUntil(tok::semi);
+      return DeclPtrTy();
+    }
+  } else if (Tok.is(tok::identifier)) {
+    // Parse identifier.
+    TargetName = Tok.getIdentifierInfo();
+    IdentLoc = ConsumeToken();
+  } else {
+    // FIXME: Use a better diagnostic here.
     Diag(Tok, diag::err_expected_ident_in_using);
+
     // If there was invalid identifier, skip to end of decl, and eat ';'.
     SkipUntil(tok::semi);
     return DeclPtrTy();
   }
   
-  // Parse identifier.
-  TargetName = Tok.getIdentifierInfo();
-  IdentLoc = ConsumeToken();
-  
   // Parse (optional) attributes (most likely GNU strong-using extension).
   if (Tok.is(tok::kw___attribute))
     AttrList = ParseAttributes();
@@ -308,7 +323,8 @@ Parser::DeclPtrTy Parser::ParseUsingDeclaration(unsigned Context,
                    AttrList ? "attributes list" : "namespace name", tok::semi);
 
   return Actions.ActOnUsingDeclaration(CurScope, UsingLoc, SS,
-                                      IdentLoc, TargetName, AttrList, IsTypeName);
+                                       IdentLoc, TargetName, Op,
+                                       AttrList, IsTypeName);
 }
 
 /// ParseStaticAssertDeclaration - Parse C++0x static_assert-declaratoion.

clang/lib/Sema/Sema.h

@@ -1574,6 +1574,7 @@ public:
                                         const CXXScopeSpec &SS,
                                         SourceLocation IdentLoc,
                                         IdentifierInfo *TargetName,
+                                        OverloadedOperatorKind Op,
                                         AttributeList *AttrList,
                                         bool IsTypeName);
   

clang/lib/Sema/SemaDeclCXX.cpp

@@ -1785,18 +1785,24 @@ Sema::DeclPtrTy Sema::ActOnUsingDeclaration(Scope *S,
                                           const CXXScopeSpec &SS,
                                           SourceLocation IdentLoc,
                                           IdentifierInfo *TargetName,
+                                          OverloadedOperatorKind Op,
                                           AttributeList *AttrList,
                                           bool IsTypeName) {
   assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
-  assert(TargetName && "Invalid TargetName.");
+  assert(TargetName || Op && "Invalid TargetName.");
   assert(IdentLoc.isValid() && "Invalid TargetName location.");
   assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
 
   UsingDecl *UsingAlias = 0;
 
+  DeclarationName Name;
+  if (TargetName)
+    Name = TargetName;
+  else
+    Name = Context.DeclarationNames.getCXXOperatorName(Op);
+  
   // Lookup target name.
-  LookupResult R = LookupParsedName(S, &SS, TargetName,
-                                    LookupOrdinaryName, false);
+  LookupResult R = LookupParsedName(S, &SS, Name, LookupOrdinaryName, false);
 
   if (NamedDecl *NS = R) {
     if (IsTypeName && !isa<TypeDecl>(NS)) {

clang/test/SemaCXX/using-decl-pr4441.cpp

@@ -0,0 +1,8 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+namespace A {
+    struct B { };
+    void operator+(B,B);
+}
+
+using A::operator+;