[libcxx-commits] [libcxx] [libc++] Add basic constant folding for std::format (PR #107197)

[Louis Dionne via libcxx-commits]

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@@ -448,13 +450,44 @@ format_to(_OutIt __out_it, wformat_string<_Args...> __fmt, _Args&&... __args) {
 }
 #  endif
 
+template <class _CharT>
+[[nodiscard]] _LIBCPP_HIDE_FROM_ABI optional<basic_string<_CharT>> __try_constant_folding(
+    basic_string_view<_CharT> __fmt,
+    basic_format_args<basic_format_context<back_insert_iterator<__format::__output_buffer<_CharT>>, _CharT>> __args) {
+  return nullopt;
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ldionne wrote:

That seems unintended.

https://github.com/llvm/llvm-project/pull/107197