[thread-safety] give full traces for read/write races

Summary:
Before, `trace_of_pname` only grabbed unprotected writes from the summary, so the traces ending in an unprotected read were truncated.
We now look at reads too when appropriate.

Reviewed By: peterogithub

Differential Revision: D4719740

fbshipit-source-id: 28f6e63

infer/src/checkers/ThreadSafety.ml

@@ -1089,11 +1089,12 @@ let pp_accesses_sink fmt ~is_write_access sink =
      else snd access_path)
 
 (* trace is really a set of accesses*)
-let report_thread_safety_violations ( _, tenv, pname, pdesc) make_description trace threaded tab =
+let report_thread_safety_violations
+    ( _, tenv, pname, pdesc) ~get_unsafe_accesses make_description trace threaded tab =
   let open ThreadSafetyDomain in
   let trace_of_pname callee_pname =
     match Summary.read_summary pdesc callee_pname with
-    | Some (_, _, accesses, _) -> get_possibly_unsafe_writes accesses
+    | Some (_, _, accesses, _) -> get_unsafe_accesses accesses
     | _ -> PathDomain.empty in
   let report_one_path ((_, sinks) as path) =
     let initial_sink, _ = List.last_exn sinks in
@@ -1168,7 +1169,9 @@ let report_reads proc_env reads threaded tab =
   let racy_reads =
     ThreadSafetyDomain.PathDomain.update_sinks reads racy_read_sinks
   in
-  report_thread_safety_violations proc_env
+  report_thread_safety_violations
+    proc_env
+    ~get_unsafe_accesses:get_possibly_unsafe_reads
     make_read_write_race_description
     racy_reads
     threaded
@@ -1254,10 +1257,15 @@ let process_results_table file_env tab =
            let stripped_unsafe_reads = strip_reads_that_have_co_located_write
                unsafe_reads
                unsafe_writes in
-           (if not threaded then (*don't report writes for threaded; TODO to extend this*)
+           if not threaded
+           then (*don't report writes for threaded; TODO to extend this*)
              report_thread_safety_violations
-                proc_env make_unprotected_write_description unsafe_writes threaded tab
+               proc_env
-           );
+               ~get_unsafe_accesses:get_possibly_unsafe_writes
+               make_unprotected_write_description
+               unsafe_writes
+               threaded
+               tab;
            report_reads proc_env stripped_unsafe_reads threaded tab
          end
     )

infer/tests/codetoanalyze/java/threadsafety/ReadWriteRaces.java

@@ -55,6 +55,14 @@ class ReadWriteRaces{
     return field1;
   }
 
+  private Object unprotectedReadInCallee() {
+    return field1;
+  }
+
+  public Object callUnprotecteReadInCallee() {
+    return unprotectedReadInCallee();
+  }
+
   public void syncWrite2() {
     synchronized(this) {
       field2 = new Object();

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

@@ -59,6 +59,7 @@ codetoanalyze/java/threadsafety/Ownership.java, void Ownership.writeToNotOwnedIn
 codetoanalyze/java/threadsafety/Ownership.java, void Ownership.writeToNotOwnedInCalleeBad3(Obj), 1, THREAD_SAFETY_VIOLATION, [call to void Ownership.callWriteToFormal(Obj),call to void Ownership.writeToFormal(Obj),access to codetoanalyze.java.checkers.Obj.f]
 codetoanalyze/java/threadsafety/Ownership.java, void Ownership.writeToOwnedInCalleeOk2(), 4, THREAD_SAFETY_VIOLATION, [access to codetoanalyze.java.checkers.Ownership.field]
 codetoanalyze/java/threadsafety/RaceWithMainThread.java, void RaceWithMainThread.read_unprotected_unthreaded_Bad(), 2, THREAD_SAFETY_VIOLATION, [access to codetoanalyze.java.checkers.RaceWithMainThread.f]
+codetoanalyze/java/threadsafety/ReadWriteRaces.java, Object ReadWriteRaces.callUnprotecteReadInCallee(), 1, THREAD_SAFETY_VIOLATION, [call to Object ReadWriteRaces.unprotectedReadInCallee(),access to codetoanalyze.java.checkers.ReadWriteRaces.field1]
 codetoanalyze/java/threadsafety/ReadWriteRaces.java, Object ReadWriteRaces.unprotectedRead1(), 1, THREAD_SAFETY_VIOLATION, [access to codetoanalyze.java.checkers.ReadWriteRaces.field1]
 codetoanalyze/java/threadsafety/ReadWriteRaces.java, Object ReadWriteRaces.unprotectedRead2(), 1, THREAD_SAFETY_VIOLATION, [access to codetoanalyze.java.checkers.ReadWriteRaces.field2]
 codetoanalyze/java/threadsafety/ReadWriteRaces.java, Object ReadWriteRaces.unprotectedRead3(), 1, THREAD_SAFETY_VIOLATION, [access to codetoanalyze.java.checkers.ReadWriteRaces.field3]