[PATCH] D45476: [C++2a] Implement operator<=> CodeGen and ExprConstant

[Eric Fiselier via Phabricator via cfe-commits]

EricWF added inline comments.


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Comment at: include/clang/AST/ComparisonCategories.h:77-78
+  ///   comparison category. For example 'std::strong_equality::equal'
+  const DeclRefExpr *getResultValue(ComparisonCategoryResult ValueKind) const {
+    const DeclRefExpr *DR = getResultValueUnsafe(ValueKind);
+    assert(DR &&
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rsmith wrote:
> EricWF wrote:
> > rsmith wrote:
> > > This should deal in `DeclRefExpr*`s, not `NamedDecl*`s. We don't have an expression naming the comparison result value, and we shouldn't pretend we do.
> > I'm confused. This does deal in `DeclRefExpr*`s. I'm probably being daft. Could you clarify?
> Sorry, while editing this comment I managed to reverse it from what I meant. This should deal in NamedDecl* (or perhaps ValueDecl*) , not DeclRefExpr*.
OK, so I tried changing this to `VarDecl` but it made the `ExprConstant` and `GCExprAgg` implementations a lot harder, since we actually want to evaluate the result as a `DeclRefExpr` as we're not evaluating the actual `Decl`. 

Since we don't want to be building dummy `DeclRefExpr`s during evaluation just to throw them away, I think it makes sense to eagerly build the results as `DeclRefExpr`s.

Does that make sense?


https://reviews.llvm.org/D45476