[PATCH] D131525: [analyzer] Fix false positive in use-after-move checker

[Malavika Samak via Phabricator via cfe-commits]

This revision was automatically updated to reflect the committed changes.
Closed by commit rGc74a204826da: [analyzer] Fix false positive in use-after-move checker (authored by malavikasamak).
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D131525/new/

https://reviews.llvm.org/D131525

Files:
  clang/lib/StaticAnalyzer/Checkers/MoveChecker.cpp
  clang/test/Analysis/use-after-move.cpp


Index: clang/test/Analysis/use-after-move.cpp
===================================================================
--- clang/test/Analysis/use-after-move.cpp
+++ clang/test/Analysis/use-after-move.cpp
@@ -900,6 +900,28 @@
   }
 }
 
+void checkExplicitDestructorCalls() {
+  // The below code segments invoke the destructor twice (explicit and 
+  // implicit). While this is not a desired code behavior, it is 
+  // not the use-after-move checker's responsibility to issue such a warning.
+  {
+     B* b = new B;
+     B a = std::move(*b);
+     b->~B(); // no-warning 
+     delete b;
+  }
+  {
+    B a, b;
+    new (&a) B(reinterpret_cast<B &&>(b));
+    (&b)->~B(); // no-warning
+  }
+  {
+    B b;
+    B a  = std::move(b);
+    b.~B(); // no-warning 
+  }
+}
+
 struct MoveOnlyWithDestructor {
   MoveOnlyWithDestructor();
   ~MoveOnlyWithDestructor();
Index: clang/lib/StaticAnalyzer/Checkers/MoveChecker.cpp
===================================================================
--- clang/lib/StaticAnalyzer/Checkers/MoveChecker.cpp
+++ clang/lib/StaticAnalyzer/Checkers/MoveChecker.cpp
@@ -618,10 +618,6 @@
   if (!IC)
     return;
 
-  // Calling a destructor on a moved object is fine.
-  if (isa<CXXDestructorCall>(IC))
-    return;
-
   const MemRegion *ThisRegion = IC->getCXXThisVal().getAsRegion();
   if (!ThisRegion)
     return;
@@ -631,6 +627,10 @@
   if (!MethodDecl)
     return;
 
+  // Calling a destructor on a moved object is fine.
+  if (isa<CXXDestructorDecl>(MethodDecl))
+    return;
+
   // We want to investigate the whole object, not only sub-object of a parent
   // class in which the encountered method defined.
   ThisRegion = ThisRegion->getMostDerivedObjectRegion();


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