[pulse] do not model `operator=` as assignment

Summary:
In a next diff temporaries will get destructed at the end of their
lifetimes and that naive model would be causing false positives.

The flipside is that we lose all reports on closures for now, will need
to model them separately later.

Reviewed By: mbouaziz

Differential Revision: D15695943

fbshipit-source-id: c2c482c02

infer/src/pulse/Pulse.ml

@@ -75,7 +75,7 @@ module PulseTransferFunctions = struct
         >>= PulseOperations.havoc [crumb] loc lhs_access
 
 
-  let exec_unknown_call summary _ret (call : HilInstr.call) (actuals : HilExp.t list) _flags
+  let exec_unknown_call _summary _ret (call : HilInstr.call) (actuals : HilExp.t list) _flags
       call_loc astate =
     let read_all args astate =
       PulseOperations.read_all call_loc (List.concat_map args ~f:HilExp.get_access_exprs) astate
@@ -94,11 +94,6 @@ module PulseTransferFunctions = struct
       when Typ.Procname.ObjC_Cpp.is_operator_equal callee_pname -> (
         L.d_printfln "operator= detected@." ;
         match actuals with
-        (* We want to assign *lhs to *rhs when rhs is materialized temporary created in constructor *)
-        | [AccessExpression lhs; HilExp.AccessExpression (AddressOf (Base rhs_base as rhs_exp))]
-          when Var.is_cpp_temporary (fst rhs_base) ->
-            let lhs_deref = HilExp.AccessExpression.dereference lhs in
-            exec_assign summary lhs_deref (HilExp.AccessExpression rhs_exp) call_loc astate
         (* copy assignment *)
         | [AccessExpression lhs; HilExp.AccessExpression rhs] ->
             let lhs_deref = HilExp.AccessExpression.dereference lhs in

infer/tests/codetoanalyze/cpp/pulse/closures.cpp

@@ -13,7 +13,7 @@ struct S {
   ~S() {}
 };
 
-int ref_capture_destroy_invoke_bad() {
+int FN_ref_capture_destroy_invoke_bad() {
   std::function<int()> f;
   {
     S s;
@@ -22,7 +22,7 @@ int ref_capture_destroy_invoke_bad() {
   return f(); // s used here
 }
 
-int implicit_ref_capture_destroy_invoke_bad() {
+int FN_implicit_ref_capture_destroy_invoke_bad() {
   std::function<int()> f;
   {
     auto s = S();

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

@@ -1,7 +1,5 @@
 codetoanalyze/cpp/pulse/basics.cpp, multiple_invalidations_branch_bad, 6, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,memory was invalidated by `delete` on `ptr` here,use-after-lifetime part of the trace starts here,invalid access to `*ptr` here]
 codetoanalyze/cpp/pulse/basics.cpp, multiple_invalidations_loop_bad, 3, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,memory was invalidated by `delete` on `ptr` here,use-after-lifetime part of the trace starts here,invalid access to `ptr` here]
-codetoanalyze/cpp/pulse/closures.cpp, implicit_ref_capture_destroy_invoke_bad, 6, USE_AFTER_LIFETIME, no_bucket, ERROR, [invalidation part of the trace starts here,memory is the address of a stack variable `s` whose lifetime has ended here,use-after-lifetime part of the trace starts here,`&s` captured as `s`,invalid access to `&f` here]
-codetoanalyze/cpp/pulse/closures.cpp, ref_capture_destroy_invoke_bad, 6, USE_AFTER_LIFETIME, no_bucket, ERROR, [invalidation part of the trace starts here,memory is the address of a stack variable `s` whose lifetime has ended here,use-after-lifetime part of the trace starts here,`&s` captured as `s`,invalid access to `&f` here]
 codetoanalyze/cpp/pulse/deduplication.cpp, deduplication::SomeTemplatedClass<int*>::lifetime_error_bad, 2, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,when calling `templated_wrapper_delete_ok` here,memory was invalidated by `delete` on `a` here,use-after-lifetime part of the trace starts here,when calling `templated_wrapper_access_ok` here,invalid access to `a->f` here]
 codetoanalyze/cpp/pulse/deduplication.cpp, deduplication::SomeTemplatedClass<int>::lifetime_error_bad, 2, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,when calling `templated_wrapper_delete_ok` here,memory was invalidated by `delete` on `a` here,use-after-lifetime part of the trace starts here,when calling `templated_wrapper_access_ok` here,invalid access to `a->f` here]
 codetoanalyze/cpp/pulse/deduplication.cpp, deduplication::templated_function_bad<_Bool>, 3, USE_AFTER_DELETE, no_bucket, ERROR, [invalidation part of the trace starts here,when calling `deduplication::templated_delete_function` here,memory was invalidated by `delete` on `a` here,use-after-lifetime part of the trace starts here,assigned to `a`,when calling `deduplication::templated_access_function` here,invalid access to `a->f` here]