[pulse][objcpp][nullptr] An example of false positive

Reviewed By: jvillard

Differential Revision: D28994794

fbshipit-source-id: a71df8d9b

infer/tests/codetoanalyze/objcpp/pulse/NPEBasic.mm

@@ -62,6 +62,18 @@
   return nil;
 }
 
++ (instancetype)sharedInstance {
+  static SomeObject* shared;
+  static dispatch_once_t onceToken;
+  dispatch_once(&onceToken, ^{
+    auto obj = [SomeObject unknown];
+    if (obj) {
+      shared = [SomeObject new];
+    }
+  });
+  return shared;
+}
+
 @end
 
 int dereferenceNilBad() {
@@ -451,3 +463,10 @@ void arrayWithObjects(id object) {
 void arrayWithObjectsOk() { arrayWithObjects(@"obj"); }
 
 void FN_arrayWithObjectsNilBad() { arrayWithObjects(nil); }
+
+std::shared_ptr<int> unknown_call_twice_FP() {
+  if (![SomeObject sharedInstance]) {
+    return std::make_shared<int>(0);
+  }
+  return [[SomeObject sharedInstance] returnsnonPOD];
+}

infer/tests/codetoanalyze/objcpp/pulse/issues.exp

@@ -30,5 +30,6 @@ codetoanalyze/objcpp/pulse/NPEBasic.mm, testNilMessagingForModelNilNilOK_FP, 0,
 codetoanalyze/objcpp/pulse/NPEBasic.mm, testNilMessagingForModelNotNilDictBad, 1, NIL_INSERTION_INTO_COLLECTION, no_bucket, ERROR, [is the null pointer,when calling `addObjectInDict` here,parameter `value` of addObjectInDict,in call to `NSMutableDictionary.setObject:forKey:` (modelled),invalid access occurs here]
 codetoanalyze/objcpp/pulse/NPEBasic.mm, testNonPODTraceBad, 2, NIL_MESSAGING_TO_NON_POD, no_bucket, ERROR, [in call to `SomeObject.returnsNil`,is the null pointer,returned,return from call to `SomeObject.returnsNil`,in call to `SomeObject.get`,parameter `self` of SomeObject.get,a message sent to nil returns nil,return from call to `SomeObject.get`,assigned,when calling `SomeObject.returnsnonPOD` here,parameter `self` of SomeObject.returnsnonPOD,invalid access occurs here]
 codetoanalyze/objcpp/pulse/NPEBasic.mm, testTraceBad, 3, NULLPTR_DEREFERENCE, no_bucket, ERROR, [is the null pointer,assigned,in call to `SomeObject.getXPtr`,parameter `self` of SomeObject.getXPtr,a message sent to nil returns nil,return from call to `SomeObject.getXPtr`,assigned,invalid access occurs here]
+codetoanalyze/objcpp/pulse/NPEBasic.mm, unknown_call_twice_FP, 4, NIL_MESSAGING_TO_NON_POD, no_bucket, ERROR, [in call to `SomeObject.sharedInstance`,is the null pointer,assigned,returned,return from call to `SomeObject.sharedInstance`,when calling `SomeObject.returnsnonPOD` here,parameter `self` of SomeObject.returnsnonPOD,invalid access occurs here]
 codetoanalyze/objcpp/pulse/use_after_delete.mm, PulseTest.deref_deleted_in_objc_method_bad, 3, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,allocated by call to `new` (modelled),assigned,was invalidated by `delete`,use-after-lifetime part of the trace starts here,allocated by call to `new` (modelled),assigned,when calling `Simple::Simple` here,parameter `__param_0` of Simple::Simple,invalid access occurs here]
 codetoanalyze/objcpp/pulse/use_after_delete.mm, deref_deleted_bad, 3, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,allocated by call to `new` (modelled),assigned,was invalidated by `delete`,use-after-lifetime part of the trace starts here,allocated by call to `new` (modelled),assigned,when calling `Simple::Simple` here,parameter `__param_0` of Simple::Simple,invalid access occurs here]