[clang] [clang] Introduce [[clang::lifetime_capture_by(X)]] (PR #111499)

[Haojian Wu via cfe-commits]

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@@ -1760,6 +1760,10 @@ class Sema final : public SemaBase {
   /// Add [[gsl::Pointer]] attributes for std:: types.
   void inferGslPointerAttribute(TypedefNameDecl *TD);
 
+  LifetimeCaptureByAttr *ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
+                                                    StringRef ParamName);
+  void LazyProcessLifetimeCaptureByParams(FunctionDecl *FD);
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hokein wrote:

nit: add some comments (it is not clear to me why it is lazy).

https://github.com/llvm/llvm-project/pull/111499