[libcxx-commits] [libcxx] [libcxx] [regex] add `[[__fallthrough__]]` to suppress fallthrough warning (PR #100821)

[Louis Dionne via libcxx-commits]

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@@ -3921,7 +3921,7 @@ _ForwardIterator basic_regex<_CharT, _Traits>::__parse_character_escape(
       if (__hd == -1)
         __throw_regex_error<regex_constants::error_escape>();
       __sum = 16 * __sum + static_cast<unsigned>(__hd);
-      // fallthrough
+      [[__fallthrough__]];
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ldionne wrote:

The CI failure is caused by AppleClang not accepting this syntax of attributes in C++03 mode. Can you use `_LIBCPP_FALLTHROUGH` instead?

https://github.com/llvm/llvm-project/pull/100821