[PATCH] D97183: [analyzer] Add NoteTag for smart-ptr get()

[Deep Majumder via Phabricator via cfe-commits]

RedDocMD created this revision.
RedDocMD added reviewers: NoQ, vsavchenko, dcoughlin.
Herald added subscribers: steakhal, ASDenysPetrov, martong, Charusso, dkrupp, donat.nagy, Szelethus, mikhail.ramalho, a.sidorin, szepet, baloghadamsoftware, xazax.hun.
RedDocMD requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Removed a TODO by adding a note-tag to explain where the
raw pointer came from.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D97183

Files:
  clang/lib/StaticAnalyzer/Checkers/SmartPtrModeling.cpp
  clang/test/Analysis/smart-ptr-text-output.cpp


Index: clang/test/Analysis/smart-ptr-text-output.cpp
===================================================================
--- clang/test/Analysis/smart-ptr-text-output.cpp
+++ clang/test/Analysis/smart-ptr-text-output.cpp
@@ -306,7 +306,7 @@
 };
 
 void derefAfterBranchingOnUnknownInnerPtr(std::unique_ptr<A> P) {
-  A *RP = P.get();
+  A *RP = P.get(); // expected-note {{Obtained null inner pointer from 'P'}}
   if (!RP) { // expected-note {{Assuming 'RP' is null}}
     // expected-note at -1 {{Taking true branch}}
     P->foo(); // expected-warning {{Dereference of null smart pointer 'P' [alpha.cplusplus.SmartPtr]}}
Index: clang/lib/StaticAnalyzer/Checkers/SmartPtrModeling.cpp
===================================================================
--- clang/lib/StaticAnalyzer/Checkers/SmartPtrModeling.cpp
+++ clang/lib/StaticAnalyzer/Checkers/SmartPtrModeling.cpp
@@ -457,8 +457,15 @@
 
   State = State->BindExpr(Call.getOriginExpr(), C.getLocationContext(),
                           InnerPointerVal);
-  // TODO: Add NoteTag, for how the raw pointer got using 'get' method.
-  C.addTransition(State);
+
+  C.addTransition(State, C.getNoteTag([ThisRegion](PathSensitiveBugReport &BR,
+                                                   llvm::raw_ostream &OS) {
+    if (&BR.getBugType() != smartptr::getNullDereferenceBugType() ||
+        !BR.isInteresting(ThisRegion))
+      return;
+    OS << "Obtained null inner pointer from";
+    checkAndPrettyPrintRegion(OS, ThisRegion);
+  }));
 }
 
 bool SmartPtrModeling::handleAssignOp(const CallEvent &Call,


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D97183.325383.patch
Type: text/x-patch
Size: 1564 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20210222/64e9e16e/attachment-0001.bin>