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

[Eric Fiselier via Phabricator via cfe-commits]

EricWF marked 3 inline comments as done.
EricWF added inline comments.


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Comment at: lib/Sema/SemaExpr.cpp:9816
+    RHS = S.ImpCastExprToType(RHS.get(), Type, CK_BitCast);
+  } else {
+    // C++2a [expr.spaceship]p4
----------------
rsmith wrote:
> We still need to apply the usual arithmetic conversions after converting enumerations to their underlying types (eg, `<=>` on `enum E : char` converts the operands first to `char` then to `int`). You could remove the `else` here and make this stuff unconditional, but it's probably better to sidestep the extra work and convert directly to the promoted type of the enum's underlying type.
Do we still do usual arithmetic conversions if we have two enumerations of the same type?


https://reviews.llvm.org/D45476