[PATCH] D100713: [clang] NFC: refactor multiple implementations of getDecltypeForParenthesizedExpr

[Richard Smith - zygoloid via Phabricator via cfe-commits]

rsmith added inline comments.


================
Comment at: clang/lib/AST/ASTContext.cpp:5461
+QualType ASTContext::getDecltypeForParenthesizedExpr(const Expr *e) const {
+  if (!e)
+    return VoidTy;
----------------
This check doesn't seem like it belongs here.


================
Comment at: clang/lib/Sema/SemaExprCXX.cpp:5845
+  if (!To->isRValue()) {
+    QualType T = Self.Context.getDecltypeForParenthesizedExpr(To);
     InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
----------------
mizvekov wrote:
> aaronpuchert wrote:
> > mizvekov wrote:
> > > aaronpuchert wrote:
> > > > The quote doesn't reference parenthesized expressions, isn't this just coincidentally the same thing?
> > > It's fundamentally the same thing. The `getDecltypeForParenthesizedExpr` name is what I tried to keep, I don't have better ideas there.
> > What this is doing is pointwise equal to `getDecltypeForParenthesizedExpr`, but there is no parenthesized expression, and no `decltype`. There is a quote from the standard that defines this separately (by now this seems to be [[http://eel.is/c++draft/expr.cond#4|expr.cond#4]]), and there are some differences especially in the prvalue case. So I'm not sure this helps.
> Here for XValue and and LValue, the rules are exactly the same as https://eel.is/c++draft/dcl.type.decltype#1.
> And the original code here even already special cases it...
> 
> I am sure there is some way we can agree that we should not repeat the code just because the standard did not bother to give a name to this part of the rules... And again I think it is no coincidence that it makes sense to perform the same changes in all these cases.
Maybe we can find a more general name for this functionality that doesn't mention `decltype`. Perhaps something like `getReferenceQualifiedType`?


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  https://reviews.llvm.org/D100713/new/

https://reviews.llvm.org/D100713