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

[Kashika Akhouri via cfe-commits]

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@@ -1202,5 +1284,198 @@ TEST_F(LifetimeAnalysisTest, LivenessOutsideLoop) {
   EXPECT_THAT(Origins({"p"}), MaybeLiveAt("p1"));
 }
 
+TEST_F(LifetimeAnalysisTest, SimpleReturnStackAddress) {
+  SetupTest(R"(
+    MyObj* target() {
+      MyObj s;
+      MyObj* p = &s;
+      POINT(p1);
+      return p;
+    }
+  )");
+  EXPECT_THAT("s", HasLiveLoanAtExpiry("p1"));
+}
+
+TEST_F(LifetimeAnalysisTest, ConditionalAssignUnconditionalReturn) {
+  SetupTest(R"(
+    MyObj* target(bool c) {
+      MyObj s1;
+      MyObj* p = nullptr;
+      if (c) {
+        p = &s1;
+      }
+      POINT(P);
+      return p;
+    }
+  )");
+  EXPECT_THAT("s1", HasLiveLoanAtExpiry("P"));
+}
+
----------------
kashika0112 wrote:

Done

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