[clang] [LifetimeSafety] Warn on incorrectly placed `[[clang::lifetimebound]]` attributes (PR #196144)

[Utkarsh Saxena via cfe-commits]

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@@ -624,12 +624,19 @@ Warning to detect invalidation of references.
   }];
 }
 
+def LifetimeSafetyLifetimeboundViolation : DiagGroup<"lifetime-safety-lifetimebound-violation"> {
+  code Documentation = [{
+Warning to detect lifetimebound violations introduced by marking parameter as lifetimebound but not returning it in any way.
+  }];
+}
+
 def LifetimeSafetyPermissive : DiagGroup<"lifetime-safety-permissive",
                                          [LifetimeSafetyUseAfterScope,
                                          LifetimeSafetyReturnStackAddr,
                                          LifetimeSafetyDanglingField,
                                          LifetimeSafetyDanglingGlobal,
-                                         LifetimeSafetyUseAfterFree]>;
+                                         LifetimeSafetyUseAfterFree,
+                                         LifetimeSafetyLifetimeboundViolation]>;
 
 def LifetimeSafetyStrict : DiagGroup<"lifetime-safety-strict",
                                     [LifetimeSafetyPermissive,
----------------
usx95 wrote:

<!--__GRAPHITE_HTML_TAG_START__--><p class='graphite__hidden'><i>[Re: lines +675 to +681]</i></p><!--__GRAPHITE_HTML_TAG_END__-->
Please add the warning to this group.
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https://github.com/llvm/llvm-project/pull/196144