Default argument cleanups and minor improvements, patch by

Doug Gregor!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@49598 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 60 insertions, 55 deletions

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index 3211e22890..89440c0cf4 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -25,63 +25,68 @@ using namespace clang;
 // CheckDefaultArgumentVisitor
 //===----------------------------------------------------------------------===//
 
-/// CheckDefaultArgumentVisitor - Traverses the default argument of a
-/// parameter to determine whether it contains any ill-formed
-/// subexpressions. For example, this will diagnose the use of local
-/// variables or parameters within the default argument expression.
-class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 
-  : public StmtVisitor<CheckDefaultArgumentVisitor, bool>
-{
-  Sema *S;
-
-public:
-  explicit CheckDefaultArgumentVisitor(Sema *s) : S(s) {}
-
-  bool VisitExpr(Expr *Node);
-  bool VisitDeclRefExpr(DeclRefExpr *DRE);
-};
-
-/// VisitExpr - Visit all of the children of this expression.
-bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
-  bool IsInvalid = false;
-  for (Stmt::child_iterator first = Node->child_begin(), 
-                            last = Node->child_end();
-       first != last; ++first)
-    IsInvalid |= Visit(*first);
-
-  return IsInvalid;
-}
-
-/// VisitDeclRefExpr - Visit a reference to a declaration, to
-/// determine whether this declaration can be used in the default
-/// argument expression.
-bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
-  ValueDecl *Decl = DRE->getDecl();
-  if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
-    // C++ [dcl.fct.default]p9
-    //   Default arguments are evaluated each time the function is
-    //   called. The order of evaluation of function arguments is
-    //   unspecified. Consequently, parameters of a function shall not
-    //   be used in default argument expressions, even if they are not
-    //   evaluated. Parameters of a function declared before a default
-    //   argument expression are in scope and can hide namespace and
-    //   class member names.
-    return S->Diag(DRE->getSourceRange().getBegin(), 
-                   diag::err_param_default_argument_references_param,
-                   Param->getName());
-  } else if (BlockVarDecl *BlockVar = dyn_cast<BlockVarDecl>(Decl)) {
-    // C++ [dcl.fct.default]p7
-    //   Local variables shall not be used in default argument
-    //   expressions.
-    return S->Diag(DRE->getSourceRange().getBegin(), 
-                   diag::err_param_default_argument_references_local,
-                   BlockVar->getName());
+namespace {
+  /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
+  /// the default argument of a parameter to determine whether it
+  /// contains any ill-formed subexpressions. For example, this will
+  /// diagnose the use of local variables or parameters within the
+  /// default argument expression.
+  class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 
+    : public StmtVisitor<CheckDefaultArgumentVisitor, bool>
+  {
+    Expr *DefaultArg;
+    Sema *S;
+
+  public:
+    CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) 
+      : DefaultArg(defarg), S(s) {}
+
+    bool VisitExpr(Expr *Node);
+    bool VisitDeclRefExpr(DeclRefExpr *DRE);
+  };
+
+  /// VisitExpr - Visit all of the children of this expression.
+  bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
+    bool IsInvalid = false;
+    for (Stmt::child_iterator first = Node->child_begin(), 
+           last = Node->child_end();
+         first != last; ++first)
+      IsInvalid |= Visit(*first);
+
+    return IsInvalid;
   }
 
-  // FIXME: when Clang has support for member functions, "this"
-  // will also need to be diagnosted.
+  /// VisitDeclRefExpr - Visit a reference to a declaration, to
+  /// determine whether this declaration can be used in the default
+  /// argument expression.
+  bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
+    ValueDecl *Decl = DRE->getDecl();
+    if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
+      // C++ [dcl.fct.default]p9
+      //   Default arguments are evaluated each time the function is
+      //   called. The order of evaluation of function arguments is
+      //   unspecified. Consequently, parameters of a function shall not
+      //   be used in default argument expressions, even if they are not
+      //   evaluated. Parameters of a function declared before a default
+      //   argument expression are in scope and can hide namespace and
+      //   class member names.
+      return S->Diag(DRE->getSourceRange().getBegin(), 
+                     diag::err_param_default_argument_references_param,
+                     Param->getName(), DefaultArg->getSourceRange());
+    } else if (BlockVarDecl *BlockVar = dyn_cast<BlockVarDecl>(Decl)) {
+      // C++ [dcl.fct.default]p7
+      //   Local variables shall not be used in default argument
+      //   expressions.
+      return S->Diag(DRE->getSourceRange().getBegin(), 
+                     diag::err_param_default_argument_references_local,
+                     BlockVar->getName(), DefaultArg->getSourceRange());
+    }
 
-  return false;
+    // FIXME: when Clang has support for member functions, "this"
+    // will also need to be diagnosed.
+
+    return false;
+  }
 }
 
 /// ActOnParamDefaultArgument - Check whether the default argument
@@ -135,7 +140,7 @@ Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc,
   //   declarator or abstract-declarator of a parameter-declaration.
 
   // Check that the default argument is well-formed
-  CheckDefaultArgumentVisitor DefaultArgChecker(this);
+  CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this);
   if (DefaultArgChecker.Visit(DefaultArg.get()))
     return;