[cfe-dev] RecursiveASTVisitor and template instantiations

[Benoit Belley]

Hi Everyone,

I am trying to write a custom static analyzer check for Clang. In my checker, I need to traverse all of the template instantiations because I need to know how function calls made by template instantiations are actually resolved.

I am using the RecursiveASTVisitor to achieve this. Unfortunately, the RecursiveASTVisitor does not traverse template instantiations by default and I had to customize it. I was able to achieve this customization all in my derived class, with the exception of redeclaring RecursiveASTVisitor::TraverseCXXRecordHelper() protected instead of private. Please look below for the code.

I am wondering if :

   a) Clang has another visitor better suited for what I am trying to achieve, or if

   b) it would be a good idea to augment the RecursiveASTVisitor class to optionally visit the template instantiations. 

I am willing to submit a patch for option b) if others also agree that this would a useful improvement.

Thanks for your help,
Benoit

-----------

Here’s what my current solution looks like for traversing template instantiations:

class RecursiveASTVisitorWithInstantiations :
  public RecursiveASTVisitor<RecursiveASTVisitorWithInstantiations> {

  typedef RecursiveASTVisitor<RecursiveASTVisitorWithInstantiations> BaseClass;
    
public:

  //============================================================================
  // Traversal functions for template instantiations
  //============================================================================

  // RecursiveASTVisitor skips the traversal of template
  // instantiations because these are not part of the source code. We
  // therefore have to reimplement a few of these functions to
  // traverse all of the AST.

  virtual bool TraverseFunctionTemplateDecl (FunctionTemplateDecl *D)
  {
    {
      if (!BaseClass::TraverseFunctionTemplateDecl(D)) {
        return false;
      }
    }

    {
      FunctionTemplateDecl::spec_iterator end = D->spec_end();
      for (FunctionTemplateDecl::spec_iterator it = D->spec_begin(); it != end; ++it) {
        if ( !TraverseFunctionDecl(*it) ) {
          return false;
        }
      }
    }

    return true;
  }

  virtual bool TraverseClassTemplateSpecializationDecl(ClassTemplateSpecializationDecl *D)
  {
    if (!getDerived().WalkUpFromClassTemplateSpecializationDecl (D)) {
      return false;
    }
    if (!getDerived().TraverseCXXRecordHelper(D)) {
      return false;
    }
    if (!getDerived().TraverseDeclContextHelper(dyn_cast<DeclContext>(D))) {
      return false;
    }
    return true;
  }

  virtual bool TraverseClassTemplateDecl (ClassTemplateDecl *D)
  {
    {
      if (!BaseClass::TraverseClassTemplateDecl(D)) {
        return false;
      }
    }

    {
      ClassTemplateDecl::spec_iterator end = D->spec_end();
      for (ClassTemplateDecl::spec_iterator it = D->spec_begin(); it != end; ++it) {
        if ( !TraverseClassTemplateSpecializationDecl(*it) ) {
          return false;
        }
      }
    }

    {
      ClassTemplateDecl::partial_spec_iterator end = D->partial_spec_end();
      for (ClassTemplateDecl::partial_spec_iterator it = D->partial_spec_begin(); it != end; ++it) {
        if ( !TraverseClassTemplatePartialSpecializationDecl(*it) ) {
          return false;
        }
      }
    }

    return true;
  }

}


 

Thanks for you help,
Benoit
 
 
Benoit Belley
Sr Principal Developer
M&E-Product Development Group    
 
Autodesk Canada Inc. 
10 Rue Duke
Montreal, Quebec  H3C 2L7 
Canada
 
Direct 514 954-7154
 
 

-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.gif
Type: image/gif
Size: 651 bytes
Desc: image002.gif
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20100825/f861e5f7/attachment.gif>
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: ATT00001..txt
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20100825/f861e5f7/attachment.txt>