[libcxx] [llvm] [libc++][CI] Update to Clang-20 (PR #108761)

[Hristo Hristov via llvm-commits]

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@@ -25,8 +25,7 @@ constexpr bool test_signed() {
   constexpr auto minVal = std::numeric_limits<IntegerT>::min();
   constexpr auto maxVal = std::numeric_limits<IntegerT>::max();
 
-  // TODO(LLVM-20) remove [[maybe_unused]]  since all supported compilers support "Placeholder variables with no name"
-  [[maybe_unused]] std::same_as<IntegerT> decltype(auto) _ = std::add_sat(minVal, maxVal);
+  std::same_as<IntegerT> decltype(auto) _ = std::add_sat(minVal, maxVal);
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Zingam wrote:

Please don't do this here I have a complete an proper PR here: https://github.com/llvm/llvm-project/pull/101826

https://github.com/llvm/llvm-project/pull/108761