[libcxx-commits] [libcxx] [libc++] Ensure that `std::expected` has no tail padding (PR #69673)

[Jan Kokemüller via libcxx-commits]

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@@ -955,8 +956,17 @@ class expected {
     _LIBCPP_NO_UNIQUE_ADDRESS _ErrorType __unex_;
   };
 
+  _LIBCPP_HIDE_FROM_ABI static constexpr auto __calculate_padding() {
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jiixyj wrote:

I implemented an alternative approach to calculate the padding type that avoids zero-length arrays (still wondering if there is a more elegant way, though). I also added some tests.

https://github.com/llvm/llvm-project/pull/69673