[libcxx-commits] [libcxx] [libc++] LWG4266: `layout_stride::mapping` should treat empty mappings as exhaustive (PR #191629)

[S. B. Tam via libcxx-commits]

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@@ -307,27 +314,12 @@ class layout_stride::mapping {
   _LIBCPP_HIDE_FROM_ABI constexpr bool is_exhaustive() const noexcept {
     if constexpr (__rank_ == 0)
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cpplearner wrote:

We can always avoid computing `required_span_size()` if `is_always_exhaustive()` is `true`.

```suggestion
    if constexpr (is_always_exhaustive())
```

https://github.com/llvm/llvm-project/pull/191629