[clang] [LifetimeSafety] Warn when lifetimebound attribute is present on the definition but not on declaration (PR #197753)

[via cfe-commits]

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@@ -415,6 +416,28 @@ class LifetimeChecker {
     }
   }
 
+  void reportMisplacedLifetimebound() {
+    const FunctionDecl *FDef = dyn_cast<FunctionDecl>(FD);
+    if (!FDef)
+      return;
+
+    const FunctionDecl *FDecl = FDef->getPreviousDecl();
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NeKon69 wrote:

Would you prefer a warning on all not annotated cases or only on one? Because I have a feeling that warning on *all* cases might be too harsh, I could just add a note saying something like "another declaration here"

https://github.com/llvm/llvm-project/pull/197753