[clang] [LifetimeSafety] Introduce buildOriginFlowChain for use-after-scope (PR #199345)

[Utkarsh Saxena via cfe-commits]

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@@ -1042,9 +1069,12 @@ void operator_star_arrow_of_iterators_false_positive_no_cfg_analysis() {
   const std::string& r = (*v.begin()).second;
 
   auto temporary = []() { return std::vector<std::pair<int, std::string>>{{1, "1"}}; };
-  const char* x = temporary().begin()->second.data();   // cfg-warning {{local temporary object does not live long enough}} cfg-note {{destroyed here}}
-  const char* y = (*temporary().begin()).second.data(); // cfg-warning {{local temporary object does not live long enough}} cfg-note {{destroyed here}}
-  const std::string& z = (*temporary().begin()).second; // cfg-warning {{local temporary object does not live long enough}} cfg-note {{destroyed here}}
+  const char* x = temporary().begin()->second.data();   // cfg-warning {{local temporary object does not live long enough}} cfg-note {{destroyed here}} \
+                                                        // cfg-note 4 {{expression aliases the storage of local temporary object}}
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usx95 wrote:

nit: Can you add this example in the PR description.

https://github.com/llvm/llvm-project/pull/199345