[clang] [clang][Interp] Three-way comparisons (PR #65901)

[Erich Keane via cfe-commits]

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@@ -253,6 +253,29 @@ bool ByteCodeExprGen<Emitter>::VisitBinaryOperator(const BinaryOperator *BO) {
     return this->delegate(RHS);
   }
 
+  // Special case for C++'s three-way/spaceship operator <=>, which
+  // returns a std::strong_ordering (which is class, so doesn't have a
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erichkeane wrote:

So this isn't really true, see the rules here: https://en.cppreference.com/w/cpp/language/default_comparisons

It can end up returning a `std::weak_ordering` or `std::partial_ordering` as well.  The rest here is true, but I wanted to make sure you know, since these have slightly different semantics that I don't see handled here?

https://github.com/llvm/llvm-project/pull/65901