[clang-tools-extra] [libc] Update libc namespace clang-tidy checks (PR #98424)

[Paul Kirth via cfe-commits]

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@@ -30,20 +30,35 @@ void ImplementationInNamespaceCheck::check(
   const auto *MatchedDecl =
       Result.Nodes.getNodeAs<Decl>("child_of_translation_unit");
   const auto *NS = dyn_cast<NamespaceDecl>(MatchedDecl);
+
+  // LLVM libc declarations should be inside of a non-anonymous namespace.
   if (NS == nullptr || NS->isAnonymousNamespace()) {
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ilovepi wrote:

@PiotrZSL shouldn't his handle the anonymous namespace concern below?

https://github.com/llvm/llvm-project/pull/98424