In C++, an initializer on a variable doesn't necessarily mean it's the definition. With that in mind, rename getDefinition to getAnyInitializer (to distinguish it from getInit) and reimplement it in terms of isThisDeclarationADefinition. Update all code to use this new function.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94999 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/Decl.h

@@ -560,22 +560,19 @@ public:
 
   /// \brief Get the tentative definition that acts as the real definition in
   /// a TU. Returns null if there is a proper definition available.
-  const VarDecl *getActingDefinition() const;
   VarDecl *getActingDefinition();
+  const VarDecl *getActingDefinition() const {
+    return const_cast<VarDecl*>(this)->getActingDefinition();
+  }
 
   /// \brief Determine whether this is a tentative definition of a
   /// variable in C.
   bool isTentativeDefinitionNow() const;
 
-  /// \brief Retrieve the definition of this variable, which may come
-  /// from a previous declaration. Def will be set to the VarDecl that
-  /// contains the initializer, and the result will be that
-  /// initializer.
-  const Expr *getDefinition(const VarDecl *&Def) const;
-
-  const Expr *getDefinition() const {
-    const VarDecl* Definition;
-    return getDefinition(Definition);
+  /// \brief Get the real (not just tentative) definition for this declaration.
+  VarDecl *getDefinition();
+  const VarDecl *getDefinition() const {
+    return const_cast<VarDecl*>(this)->getDefinition();
   }
 
   /// \brief Determine whether this is or was instantiated from an out-of-line 
@@ -600,6 +597,17 @@ public:
     return false;
   }
 
+  /// getAnyInitializer - Get the initializer for this variable, no matter which
+  /// declaration it is attached to.
+  const Expr *getAnyInitializer() const {
+    const VarDecl *D;
+    return getAnyInitializer(D);
+  }
+
+  /// getAnyInitializer - Get the initializer for this variable, no matter which
+  /// declaration it is attached to. Also get that declaration.
+  const Expr *getAnyInitializer(const VarDecl *&D) const;
+
   bool hasInit() const {
     return !Init.isNull();
   }

lib/AST/Decl.cpp

@@ -522,10 +522,6 @@ VarDecl::DefinitionKind VarDecl::isThisDeclarationADefinition() const {
   return Definition;
 }
 
-const VarDecl *VarDecl::getActingDefinition() const {
-  return const_cast<VarDecl*>(this)->getActingDefinition();
-}
-
 VarDecl *VarDecl::getActingDefinition() {
   DefinitionKind Kind = isThisDeclarationADefinition();
   if (Kind != TentativeDefinition)
@@ -553,16 +549,24 @@ bool VarDecl::isTentativeDefinitionNow() const {
     if ((*I)->isThisDeclarationADefinition() == Definition)
       return false;
   }
-  return true;  
+  return true;
 }
 
-const Expr *VarDecl::getDefinition(const VarDecl *&Def) const {
+VarDecl *VarDecl::getDefinition() {
+  for (redecl_iterator I = redecls_begin(), E = redecls_end(); I != E; ++I) {
+    if ((*I)->isThisDeclarationADefinition() == Definition)
+      return *I;
+  }
+  return 0;
+}
+
+const Expr *VarDecl::getAnyInitializer(const VarDecl *&D) const {
   redecl_iterator I = redecls_begin(), E = redecls_end();
   while (I != E && !I->getInit())
     ++I;
 
   if (I != E) {
-    Def = *I;
+    D = *I;
     return I->getInit();
   }
   return 0;

lib/AST/Expr.cpp

@@ -99,8 +99,7 @@ void DeclRefExpr::computeDependence() {
   else if (VarDecl *Var = dyn_cast<VarDecl>(D)) {
     if (Var->getType()->isIntegralType() &&
         Var->getType().getCVRQualifiers() == Qualifiers::Const) {
-      const VarDecl *Def = 0;
-      if (const Expr *Init = Var->getDefinition(Def))
+      if (const Expr *Init = Var->getAnyInitializer())
         if (Init->isValueDependent())
           ValueDependent = true;
     }
@@ -1654,15 +1653,14 @@ static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) {
         if (Quals.hasVolatile() || !Quals.hasConst())
           return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation());
         
-        // Look for the definition of this variable, which will actually have
-        // an initializer.
-        const VarDecl *Def = 0;
-        const Expr *Init = Dcl->getDefinition(Def);
+        // Look for a declaration of this variable that has an initializer.
+        const VarDecl *ID = 0;
+        const Expr *Init = Dcl->getAnyInitializer(ID);
         if (Init) {
-          if (Def->isInitKnownICE()) {
+          if (ID->isInitKnownICE()) {
             // We have already checked whether this subexpression is an
             // integral constant expression.
-            if (Def->isInitICE())
+            if (ID->isInitICE())
               return NoDiag();
             else
               return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation());
@@ -1674,7 +1672,7 @@ static ICEDiag CheckICE(const Expr* E, ASTContext &Ctx) {
           //   specify a constant-initializer which shall be an integral 
           //   constant expression (5.19). In that case, the member can appear
           //   in integral constant expressions.
-          if (Def->isOutOfLine()) {
+          if (ID->isOutOfLine()) {
             Dcl->setInitKnownICE(false);
             return ICEDiag(2, cast<DeclRefExpr>(E)->getLocation());
           }

lib/AST/ExprConstant.cpp

@@ -263,8 +263,7 @@ APValue LValueExprEvaluator::VisitDeclRefExpr(DeclRefExpr *E) {
     if (!VD->getType()->isReferenceType())
       return APValue(E);
     // FIXME: Check whether VD might be overridden!
-    const VarDecl *Def = 0;
-    if (const Expr *Init = VD->getDefinition(Def))
+    if (const Expr *Init = VD->getAnyInitializer())
       return Visit(const_cast<Expr *>(Init));
   }
 
@@ -880,8 +879,7 @@ bool IntExprEvaluator::CheckReferencedDecl(const Expr* E, const Decl* D) {
   if (Info.Ctx.getCanonicalType(E->getType()).getCVRQualifiers() 
                                                         == Qualifiers::Const) {
     if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
-      const VarDecl *Def = 0;
-      if (const Expr *Init = VD->getDefinition(Def)) {
+      if (const Expr *Init = VD->getAnyInitializer()) {
         if (APValue *V = VD->getEvaluatedValue()) {
           if (V->isInt())
             return Success(V->getInt(), E);

lib/CodeGen/CodeGenModule.cpp

@@ -979,7 +979,7 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
   QualType ASTTy = D->getType();
   bool NonConstInit = false;
 
-  const Expr *InitExpr = D->getDefinition();
+  const Expr *InitExpr = D->getAnyInitializer();
   
   if (!InitExpr) {
     // This is a tentative definition; tentative definitions are

lib/Sema/SemaChecking.cpp

@@ -846,8 +846,7 @@ bool Sema::SemaCheckStringLiteral(const Expr *E, const CallExpr *TheCall,
       }
 
       if (isConstant) {
-        const VarDecl *Def = 0;
-        if (const Expr *Init = VD->getDefinition(Def))
+        if (const Expr *Init = VD->getAnyInitializer())
           return SemaCheckStringLiteral(Init, TheCall,
                                         HasVAListArg, format_idx, firstDataArg);
       }

lib/Sema/SemaDecl.cpp

@@ -2360,9 +2360,9 @@ Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC,
 
   // attributes declared post-definition are currently ignored
   if (Previous.isSingleResult()) {
-    const VarDecl *Def = 0;
-    VarDecl *PrevDecl = dyn_cast<VarDecl>(Previous.getFoundDecl());
-    if (PrevDecl && PrevDecl->getDefinition(Def) && D.hasAttributes()) {
+    VarDecl *Def = dyn_cast<VarDecl>(Previous.getFoundDecl());
+    if (Def && (Def = Def->getDefinition()) &&
+        Def != NewVD && D.hasAttributes()) {
       Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition);
       Diag(Def->getLocation(), diag::note_previous_definition);
     }
@@ -3435,8 +3435,8 @@ void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) {
                              AbstractVariableType))
     VDecl->setInvalidDecl();
 
-  const VarDecl *Def = 0;
-  if (VDecl->getDefinition(Def)) {
+  const VarDecl *Def;
+  if ((Def = VDecl->getDefinition()) && Def != VDecl) {
     Diag(VDecl->getLocation(), diag::err_redefinition)
       << VDecl->getDeclName();
     Diag(Def->getLocation(), diag::note_previous_definition);

lib/Sema/SemaDeclCXX.cpp

@@ -4062,8 +4062,8 @@ void Sema::AddCXXDirectInitializerToDecl(DeclPtrTy Dcl,
                              AbstractVariableType))
     VDecl->setInvalidDecl();
 
-  const VarDecl *Def = 0;
-  if (VDecl->getDefinition(Def)) {
+  const VarDecl *Def;
+  if ((Def = VDecl->getDefinition()) && Def != VDecl) {
     Diag(VDecl->getLocation(), diag::err_redefinition)
     << VDecl->getDeclName();
     Diag(Def->getLocation(), diag::note_previous_definition);

tools/CIndex/CIndex.cpp

@@ -1733,23 +1733,10 @@ CXCursor clang_getCursorDefinition(CXCursor C) {
   }
 
   case Decl::Var: {
-    VarDecl *Var = cast<VarDecl>(D);
-
-    // Variables with initializers have definitions.
-    const VarDecl *Def = 0;
-    if (Var->getDefinition(Def))
-      return MakeCXCursor(const_cast<VarDecl *>(Def), CXXUnit);
-
-    // extern and private_extern variables are not definitions.
-    if (Var->hasExternalStorage())
-      return clang_getNullCursor();
-
-    // In-line static data members do not have definitions.
-    if (Var->isStaticDataMember() && !Var->isOutOfLine())
-      return clang_getNullCursor();
-
-    // All other variables are themselves definitions.
-    return C;
+    // Ask the variable if it has a definition.
+    if (VarDecl *Def = cast<VarDecl>(D)->getDefinition())
+      return MakeCXCursor(Def, CXXUnit);
+    return clang_getNullCursor();
   }
    
   case Decl::FunctionTemplate: {