[cfe-dev] Patch for References

[Chris Lattner]

On Jul 14, 2007, at 2:25 AM, Bill Wendling wrote:

> On Jul 13, 2007, at 9:39 AM, Chris Lattner wrote:
>
>> I still don't think this is right.  Nothing in the subscript  
>> operator should care about arrays.  You should rely on the usual  
>> unary conversions for decaying the array to a pointer.  Perhaps  
>> you need to implement usual unary conversions for references?
>
> Ah! I understand what you're saying now. Here's a new patch  
> submission. I think it does the correct thing now. I even have the  
> correct standard citation. :-)

This patch has some of the same problems as the previous one.  For  
example:

+
+  const FunctionType *funcT = 0;
+
+  if (PT == 0) {
+    // C++ 8.5.3p1: This is a reference to a function.
+    const ReferenceType *RT = dyn_cast<ReferenceType>(qType);
+
+    if (RT) {
+      funcT = dyn_cast<FunctionType>(RT->getReferenceeType());
+
+      if (funcT == 0)
+        funcT =

...

The reference should be stripped off automatically by "implicit  
conversion handling" (See [conv], S4p3), not with explicit code in  
the call expr handler, because the callee is an rvalue.


+  if (const ReferenceType *ref = dyn_cast<ReferenceType> 
(t.getCanonicalType()))
+    t = ref->getReferenceeType(); // C++ 5p5

5p5 talks about the pointer-to-member operator, so I'm not sure how  
it is relevant.  When citing the C++ standard, please use the section  
name as well, such as "[expr.mptr.oper]".  I assume the intent is for  
these names to be stable as the standard moves forward.


-Expr::isLvalueResult Expr::isLvalue() {
+Expr::isLvalueResult Expr::isLvalue() const {

Marking this method const is fine, please commit it as a separate patch.


+  if (isa<ReferenceType>(TR.getCanonicalType())) // C++ 5p5
+    return LV_Valid;

Likewise, this citation is non-sensical, see chapter 4 for the cite  
you are looking for.

-Chris