From fae235197fe07f62c786c64129c45071a30ba400 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Tue, 16 Apr 2024 12:31:44 +0200
Subject: [PATCH] util/SpanCast: allow ReferenceAsBytes() only with
 trivially-copyable

Addd the std::has_unique_object_representations_v constraint so we
cast stuff to std::byte only if this would make sense.
---
 src/util/SpanCast.hxx | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/util/SpanCast.hxx b/src/util/SpanCast.hxx
index 10d45062c..27582433b 100644
--- a/src/util/SpanCast.hxx
+++ b/src/util/SpanCast.hxx
@@ -64,6 +64,7 @@ AsBytes(std::string_view sv) noexcept
  * Cast a reference to a fixed-size std::span<const std::byte>.
  */
 template<typename T>
+requires std::has_unique_object_representations_v<T>
 constexpr auto
 ReferenceAsBytes(const T &value) noexcept
 {
@@ -71,6 +72,7 @@ ReferenceAsBytes(const T &value) noexcept
 }
 
 template<typename T>
+requires std::has_unique_object_representations_v<T>
 constexpr auto
 ReferenceAsWritableBytes(T &value) noexcept
 {