[PATCH] D55465: Stop tracking retain count of OSObject after escape to void * / other primitive types

[George Karpenkov via Phabricator via cfe-commits]

This revision was automatically updated to reflect the committed changes.
Closed by commit rC348675: Stop tracking retain count of OSObject after escape to void * / other primitive… (authored by george.karpenkov, committed by ).
Herald added a subscriber: cfe-commits.

Changed prior to commit:
  https://reviews.llvm.org/D55465?vs=177361&id=177362#toc

Repository:
  rC Clang

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55465/new/

https://reviews.llvm.org/D55465

Files:
  lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.cpp
  test/Analysis/osobject-retain-release.cpp


Index: lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.cpp
===================================================================
--- lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.cpp
+++ lib/StaticAnalyzer/Checkers/RetainCountChecker/RetainCountChecker.cpp
@@ -574,6 +574,25 @@
   return State;
 }
 
+static bool isPointerToObject(QualType QT) {
+  QualType PT = QT->getPointeeType();
+  if (!PT.isNull())
+    if (PT->getAsCXXRecordDecl())
+      return true;
+  return false;
+}
+
+/// Whether the tracked value should be escaped on a given call.
+/// OSObjects are escaped when passed to void * / etc.
+static bool shouldEscapeArgumentOnCall(const CallEvent &CE, unsigned ArgIdx,
+                                       const RefVal *TrackedValue) {
+  if (TrackedValue->getObjKind() != RetEffect::OS)
+    return false;
+  if (ArgIdx >= CE.parameters().size())
+    return false;
+  return !isPointerToObject(CE.parameters()[ArgIdx]->getType());
+}
+
 void RetainCountChecker::checkSummary(const RetainSummary &Summ,
                                       const CallEvent &CallOrMsg,
                                       CheckerContext &C) const {
@@ -592,6 +611,10 @@
       state = updateOutParameter(state, V, Effect);
     } else if (SymbolRef Sym = V.getAsLocSymbol()) {
       if (const RefVal *T = getRefBinding(state, Sym)) {
+
+        if (shouldEscapeArgumentOnCall(CallOrMsg, idx, T))
+          Effect = StopTrackingHard;
+
         state = updateSymbol(state, Sym, *T, Effect, hasErr, C);
         if (hasErr) {
           ErrorRange = CallOrMsg.getArgSourceRange(idx);
Index: test/Analysis/osobject-retain-release.cpp
===================================================================
--- test/Analysis/osobject-retain-release.cpp
+++ test/Analysis/osobject-retain-release.cpp
@@ -89,6 +89,13 @@
   static OSObject *safeMetaCast(const OSObject *inst, const OSMetaClass *meta);
 };
 
+void escape(void *);
+
+void test_escaping_into_voidstar() {
+  OSObject *obj = new OSObject;
+  escape(obj);
+}
+
 void test_no_infinite_check_recursion(MyArray *arr) {
   OSObject *input = new OSObject;
   OSObject *o = arr->generateObject(input);


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