[clang] [clang][sema] Add nonnull attribute to builtin format functions (PR #158626)

[Erich Keane via cfe-commits]

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@@ -392,6 +392,10 @@ class Context {
   bool performsCallback(unsigned ID,
                         llvm::SmallVectorImpl<int> &Encoding) const;
 
+  /// Return true if this builtin has parameters at fixed positions
+  /// that must be non-null.
+  bool IsNonNull(unsigned ID, llvm::SmallVectorImpl<int> &Indxs) const;
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erichkeane wrote:

Also, should the `SmallVector` take `unsigned`s instead?

https://github.com/llvm/llvm-project/pull/158626