[libcxx-commits] [libcxx] [libcxx] Added segment iterator for fill (PR #104680)

[Nikolas Klauser via libcxx-commits]

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@@ -21,23 +21,64 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 // fill isn't specialized for std::memset, because the compiler already optimizes the loop to a call to std::memset.
 
-template <class _ForwardIterator, class _Tp>
+template <
+    class _ForwardIterator,
+    class _Tp,
+    __enable_if_t<
+        is_same<typename iterator_traits<_ForwardIterator>::iterator_category, forward_iterator_tag>::value ||
+            is_same<typename iterator_traits<_ForwardIterator>::iterator_category, bidirectional_iterator_tag>::value,
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philnik777 wrote:

This is wrong. Users are allowed to add their own iterator categories that derive from standard ones. You should use the `__has_x_iterator_category` utilities instead. In this case it could simply be `!__has_random_access_iterator_category<_ForwardIterator>::value`. Same below.

https://github.com/llvm/llvm-project/pull/104680