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

[Kashika Akhouri via cfe-commits]

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@@ -396,6 +396,124 @@ void loan_from_previous_iteration(MyObj safe, bool condition) {
   }             // expected-note {{destroyed here}}
 }
 
+//===----------------------------------------------------------------------===//
+// Basic Definite Use-After-Return (Return-Stack-Address) (-W...permissive)
+// These are cases where the pointer is guaranteed to be dangling at the use site.
+//===----------------------------------------------------------------------===//
+
+MyObj* simple_return_stack_address(){
+  MyObj s;      
+  MyObj* p = &s; // expected-warning {{address of stack memory is returned later}}
+  return p;      // expected-note {{returned here}}
+}
+
+const MyObj* conditional_assign_unconditional_return(const MyObj& safe, bool c){
+  MyObj s; 
+  const MyObj* p = &safe;
+  if(c){
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kashika0112 wrote:

Done

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