[llvm] [libcxx] [clang] [clang-tools-extra] [libc++][span] P2821R5: span.at() (PR #74994)

[Mark de Wever via cfe-commits]

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@@ -146,6 +147,9 @@ template<class R>
 #include <__utility/forward.h>
 #include <array>        // for array
 #include <cstddef>      // for byte
+#if _LIBCPP_STD_VER >= 26
+#  include <stdexcept>
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mordante wrote:

Typically we unconditionally include headers.

https://github.com/llvm/llvm-project/pull/74994