[clang] [C23] Implement WG14 N3037 (PR #132939)

[via cfe-commits]

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@@ -43,6 +43,9 @@ struct StructuralEquivalenceContext {
   /// key: (from, to, IgnoreTemplateParmDepth)
   using NonEquivalentDeclSet = llvm::DenseSet<std::tuple<Decl *, Decl *, int>>;
 
+  /// The language options to use for making a structural equivalence check.
+  const LangOptions &LangOpts;
+
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cor3ntin wrote:

We already have 2 ASTContext; why not use the LangOpt from there? Possibly with a small function to make it less verbose.

https://github.com/llvm/llvm-project/pull/132939