[clang] [LifetimeSafety] Read lifetimebound attribute on implicit 'this' from all redeclarations (PR #176188)

[Gábor Horváth via cfe-commits]

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@@ -45,6 +46,12 @@ bool isAssignmentOperatorLifetimeBound(const CXXMethodDecl *CMD);
 /// method or because it's a normal assignment operator.
 bool implicitObjectParamIsLifetimeBound(const FunctionDecl *FD);
 
+/// Check if a function has a lifetimebound attribute on its function type
+/// (which represents the implicit 'this' parameter for methods).
+/// Returns the attribute if found, nullptr otherwise.
+const LifetimeBoundAttr *
+getLifetimeBoundAttrFromFunctionType(const TypeSourceInfo &TSI);
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Xazax-hun wrote:

We no longer need this one in the public header, right? 

https://github.com/llvm/llvm-project/pull/176188