[ThreadSafety] Do not report if all accesses are unprotected.

Reviewed By: jberdine

Differential Revision: D5256183

fbshipit-source-id: f2f2c57

infer/src/checkers/ThreadSafety.ml

@@ -1215,11 +1215,16 @@ let report_unsafe_accesses aggregated_access_map =
           (* protected write, do nothing *)
           reported_acc
       | Access.Read, AccessPrecondition.Unprotected _ ->
-          (* unprotected read. report all writes as conflicts *)
+          (* unprotected read. report all writes as conflicts for java *)
+          (* for c++ filter out unprotected writes *)
+          let is_cpp_protected_write pre = match pre with
+            | AccessPrecondition.Unprotected _ -> Typ.Procname.is_java pname
+            | AccessPrecondition.Protected _ -> true in
           let all_writes =
             List.filter
-              ~f:(fun (other_access, _, other_threaded, _, _) ->
-                  TraceElem.is_write other_access && not (threaded && other_threaded))
+              ~f:(fun (other_access, pre, other_threaded, _, _) ->
+                  TraceElem.is_write other_access && not (threaded && other_threaded)
+                  && is_cpp_protected_write pre)
               accesses in
           if List.is_empty all_writes
           then

infer/tests/codetoanalyze/cpp/threadsafety/basics_with_mutex.cpp

@@ -1,32 +0,0 @@
-/*
- * Copyright (c) 2017 - present Facebook, Inc.
- * All rights reserved.
- *
- * This source code is licensed under the BSD style license found in the
- * LICENSE file in the root directory of this source tree. An additional grant
- * of patent rights can be found in the PATENTS file in the same directory.
- */
-
-#include <mutex>
-
-namespace basics {
-
-class BasicsWithHeader {
- public:
-  BasicsWithHeader(){};
-
-  void set(int new_value) {
-    field_1 = new_value;
-    field_2 = new_value;
-    field_3 = new_value;
-  };
-  int get1() { return field_1; };
-  int get2() { return field_2; };
-
- private:
-  int field_1;
-  int field_2;
-  int field_3;
-  std::mutex mutex_;
-};
-}

infer/tests/codetoanalyze/cpp/threadsafety/issues.exp

@@ -1,10 +1,6 @@
 codetoanalyze/cpp/threadsafety/basics.cpp, basics::Basic_get2, 3, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_written`,<Beginning of write trace>,access to `suspiciously_written`]
-codetoanalyze/cpp/threadsafety/basics.cpp, basics::Basic_get3, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `not_guarded`,<Beginning of write trace>,access to `not_guarded`]
 codetoanalyze/cpp/threadsafety/basics.cpp, basics::Basic_get4, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]
-codetoanalyze/cpp/threadsafety/basics_with_mutex.cpp, basics::BasicsWithHeader_get1, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `field_1`,<Beginning of write trace>,access to `field_1`]
-codetoanalyze/cpp/threadsafety/basics_with_mutex.cpp, basics::BasicsWithHeader_get2, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `field_2`,<Beginning of write trace>,access to `field_2`]
 codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get2, 3, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_written`,<Beginning of write trace>,access to `suspiciously_written`]
-codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get3, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `not_guarded`,<Beginning of write trace>,access to `not_guarded`]
 codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get4, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]
 codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_test1, 2, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]
 codetoanalyze/cpp/threadsafety/lock_guard_with_scope.cpp, basics::LockGuardWithScope_get3, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `not_guarded`,<Beginning of write trace>,access to `not_guarded`]