Remove second-guessing for DeclRefExprs in CallExprs

In TraverseDeclRefExpr we would exit early if we were under a
CallExpr, with the motivation that CallExpr had already handled the
relevant cases.

However, VisitCallExpr only looks specifically for reference arguments
passed to vararg functions, and ignores everything else.

Let TraverseDeclRefExpr work on all expressions, so that creating
function pointers to templates works in all contexts, including
CallExprs.

Fixes issue #425.

1 files changed, 1 insertions, 9 deletions

diff --git a/iwyu.cc b/iwyu.cc
index 196a574..8650546 100644
--- a/iwyu.cc
+++ b/iwyu.cc
@@ -899,21 +899,13 @@ class BaseAstVisitor : public RecursiveASTVisitor<Derived> {
         const_cast<CXXDestructorDecl*>(dtor), parent_type, expr);
   }
 
-  // This is to catch assigning template functions to function pointers.
+  // This is to catch function pointers to templates.
   // For instance, 'MyFunctionPtr p = &TplFn<MyClass*>;': we need to
   // expand TplFn to see if it needs full type info for MyClass.
   bool TraverseDeclRefExpr(clang::DeclRefExpr* expr) {
     if (!Base::TraverseDeclRefExpr(expr))  return false;
     if (CanIgnoreCurrentASTNode())  return true;
 
-    // If it's a normal function call, that was already handled by a
-    // CallExpr somewhere.  We want only assignments.
-    if (current_ast_node()->template ParentIsA<CallExpr>() ||
-        (current_ast_node()->template ParentIsA<ImplicitCastExpr>() &&
-         current_ast_node()->template AncestorIsA<CallExpr>(2))) {
-      return true;
-    }
-
     if (FunctionDecl* fn_decl = DynCastFrom(expr->getDecl())) {
       // If fn_decl has a class-name before it -- 'MyClass::method' --
       // it's a method pointer.