[clang] [LifetimeSafety] Detect use-after-return (PR #165370)

[Utkarsh Saxena via cfe-commits]

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@@ -10728,8 +10728,19 @@ def warn_lifetime_safety_loan_expires_permissive : Warning<
 def warn_lifetime_safety_loan_expires_strict : Warning<
    "object whose reference is captured may not live long enough">,
    InGroup<LifetimeSafetyStrict>, DefaultIgnore;
+
+def warn_lifetime_safety_return_stack_addr_permissive
+    : Warning<"returning reference to stack allocated object">,
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usx95 wrote:

nit on wording:
`address of stack memory is returned later`
and `address of stack memory maybe returned later`

https://github.com/llvm/llvm-project/pull/165370