[clang] [libcxx] [Clang] Implement CWG2369 "Ordering between constraints and substitution" (PR #102857)

[via cfe-commits]

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@@ -522,6 +522,9 @@ enum class TemplateSubstitutionKind : char {
     llvm::PointerUnion<Decl *, DeclArgumentPack *> *
     findInstantiationOf(const Decl *D);
 
+    llvm::PointerUnion<Decl *, DeclArgumentPack *> *
+    findInstantiationUnsafe(const Decl *D);
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cor3ntin wrote:

Can you add a comment explaining what this does?

https://github.com/llvm/llvm-project/pull/102857