Stub out the EmptyAction class.

llvm-svn: 38914

clang/Driver/clang.cpp

@@ -752,7 +752,7 @@ int main(int argc, char **argv) {
     //ParseFile(PP, new ParserPrintActions(PP), MainFileID);
     break;
   case ParseSyntaxOnly:              // -fsyntax-only
-    ParseFile(PP, new Action(), MainFileID);
+    ParseFile(PP, new EmptyAction(), MainFileID);
     break;
   }
   

clang/Parse/MinimalAction.cpp

@@ -0,0 +1,37 @@
+//===--- EmptyAction.cpp - Minimalistic action implementation -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements the EmptyAction interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Parse/Parser.h"
+//#include "clang/Parse/Declarations.h"
+//#include "clang/Parse/Scope.h"
+using namespace llvm;
+using namespace clang;
+
+/// isTypedefName - This looks at the IdentifierInfo::FETokenInfo field to
+/// determine whether the name is a typedef or not in this scope.
+bool EmptyAction::isTypedefName(const IdentifierInfo &II, Scope *S) const {
+  return true;
+}
+
+/// ParseDeclarator - If this is a typedef declarator, we modify the
+/// IdentifierInfo::FETokenInfo field to keep track of this fact, until S is
+/// popped.
+void EmptyAction::ParseDeclarator(SourceLocation Loc, Scope *S, Declarator &D,
+                                  ExprTy *Init) {
+}
+
+/// PopScope - When a scope is popped, if any typedefs are now out-of-scope,
+/// they are removed from the IdentifierInfo::FETokenInfo field.
+void EmptyAction::PopScope(SourceLocation Loc, Scope *S) {
+  
+}

clang/include/clang/Parse/Action.h

@@ -7,7 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-//  This file defines the Action interface.
+//  This file defines the Action and EmptyAction interface.
 //
 //===----------------------------------------------------------------------===//
 
@@ -18,10 +18,11 @@
 
 namespace llvm {
 namespace clang {
-  // Parse.
-  class Scope;
   // Semantic.
   class Declarator;
+  // Parse.
+  class Scope;
+  class Action;
 
 /// Action - As the parser reads the input file and recognizes the productions
 /// of the grammar, it invokes methods on this class to turn the parsed input
@@ -31,9 +32,9 @@ namespace clang {
 /// the parser has just done or is about to do when the method is called.  They
 /// are not requests that the actions module do the specified action.
 ///
-/// All of the methods here are optional, but you must specify information about
-/// whether something is a typedef or not in order for the parse to complete
-/// accurately.  The EmptyAction class does this bare-minimum of tracking.
+/// All of the methods here are optional except isTypedefName(), which must be
+/// specified in order for the parse to complete accurately.  The EmptyAction
+/// class does this bare-minimum of tracking to implement this functionality.
 class Action {
 public:
   /// Out-of-line virtual destructor to provide home for this class.
@@ -47,6 +48,10 @@ public:
   // Symbol table tracking callbacks.
   //===--------------------------------------------------------------------===//
   
+  /// isTypedefName - Return true if the specified identifier is a typedef name
+  /// in the current scope.
+  virtual bool isTypedefName(const IdentifierInfo &II, Scope *S) const = 0;
+  
   /// ParseDeclarator - This callback is invoked when a declarator is parsed and
   /// 'Init' specifies the initializer if any.  This is for things like:
   /// "int X = 4" or "typedef int foo".
@@ -58,6 +63,28 @@ public:
   virtual void PopScope(SourceLocation Loc, Scope *S) {}
   
 };
+
+
+/// EmptyAction - This is a simple (bare-minimum) implementation of the Action
+/// class, which only keeps track of which typedefs are in-scope.  This class is
+/// useful to subclass if clients want to implement some actions without having
+/// to reimplement all of the scoping rules.
+class EmptyAction : public Action {
+
+  /// isTypedefName - This looks at the IdentifierInfo::FETokenInfo field to
+  /// determine whether the name is a typedef or not in this scope.
+  virtual bool isTypedefName(const IdentifierInfo &II, Scope *S) const;
+  
+  /// ParseDeclarator - If this is a typedef declarator, we modify the
+  /// IdentifierInfo::FETokenInfo field to keep track of this fact, until S is
+  /// popped.
+  virtual void ParseDeclarator(SourceLocation Loc, Scope *S, Declarator &D,
+                               ExprTy *Init);
+  
+  /// PopScope - When a scope is popped, if any typedefs are now out-of-scope,
+  /// they are removed from the IdentifierInfo::FETokenInfo field.
+  virtual void PopScope(SourceLocation Loc, Scope *S);
+};
   
 }  // end namespace clang
 }  // end namespace llvm