[liveness] remove special-casing for destructor reads

Reviewed By: jeremydubreil

Differential Revision: D6569310

fbshipit-source-id: f072e05

infer/src/checkers/liveness.ml

@@ -56,10 +56,6 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
     | Sil.Load (lhs_id, _, _, _) when Ident.is_none lhs_id ->
         (* dummy deref inserted by frontend--don't count as a read *)
         astate
-    | Sil.Call (_, Exp.Const Cfun (Typ.Procname.ObjC_Cpp _ as pname), _, _, _)
-      when Typ.Procname.is_destructor pname ->
-        (* don't count destructor calls as a read *)
-        astate
     | Sil.Load (lhs_id, rhs_exp, _, _) ->
         Domain.remove (Var.of_id lhs_id) astate |> exp_add_live rhs_exp
     | Sil.Store (Lvar lhs_pvar, _, rhs_exp, _) ->
@@ -95,23 +91,7 @@ let matcher_scope_guard =
     | _ ->
         init
   in
-  let default_scope_guards =
+  let default_scope_guards = ["CKComponentScope"] in
-    [ (* C++ *)
-      "folly::RWSpinLock::ReadHolder"
-    ; "folly::RWSpinLock::WriteHolder"
-    ; "folly::ScopeGuard"
-    ; "folly::SharedMutex::ReadHolder"
-    ; "folly::SharedMutex::WriteHolder"
-    ; "folly::SharedMutexReadPriority::ReadHolder"
-    ; "folly::SharedMutexReadPriority::WriteHolder"
-    ; "folly::SharedMutexWritePriority::ReadHolder"
-    ; "folly::SharedMutexWritePriority::WriteHolder"
-    ; "folly::SpinLockGuard"
-    ; "std::lock_guard"
-    ; "std::scoped_lock"
-    ; "std::unique_lock" (* Obj-C *)
-    ; "CKComponentScope" ]
-  in
   of_json default_scope_guards Config.cxx_scope_guards
   |> QualifiedCppName.Match.of_fuzzy_qual_names
 
@@ -180,3 +160,4 @@ let checker {Callbacks.tenv; summary; proc_desc} : Specs.summary =
   in
   List.iter (CFG.nodes cfg) ~f:report_on_node ;
   summary
+

infer/tests/codetoanalyze/cpp/liveness/dead_stores.cpp

@@ -15,17 +15,6 @@ namespace infer {
 class ScopeGuard {};
 }; // namespace infer
 
-namespace folly {
-class ScopeGuard {};
-
-class SharedMutex {
- public:
-  class ReadHolder {};
-  class WriteHolder {};
-};
-
-} // namespace folly
-
 namespace dead_stores {
 
 void easy_bad() { int x = 5; }
@@ -296,15 +285,6 @@ int* sentinel_ptr_ok(int* j) {
   return i;
 }
 
-void scope_guard_ok() {
-  // realistically, it would be something like guard = folly::makeGuard();
-  folly::ScopeGuard guard;
-}
-
-void read_holder_ok() { folly::SharedMutex::ReadHolder guard; }
-
-void write_holder_ok() { folly::SharedMutex::WriteHolder guard; }
-
 void custom_scope_guard_ok() { infer::ScopeGuard guard; }
 
 struct S {
@@ -319,7 +299,7 @@ S mk_s() {
 };
 
 // s gets read by the destructor for S
-void dead_struct_value1_bad() { S s = mk_s(); }
+void FN_dead_struct_value1_bad() { S s = mk_s(); }
 
 // need to handle operator= in order to detect this case
 void FN_dead_struct_value2_bad() {
@@ -339,6 +319,10 @@ B& struct_rvalue_ref_used_ok() {
   return b;
 }
 
+struct NoDestructor {};
+
+void dead_struct_no_destructor_bad() { NoDestructor dead; }
+
 std::mutex my_mutex;
 
 void dead_lock_guard_ok() { std::lock_guard<std::mutex> lock(my_mutex); }

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

@@ -1,12 +1,12 @@
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::FP_assign_array_tricky_ok, 3, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::dead_pointer_bad, 2, DEAD_STORE, [Write of unused value]
+codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::dead_struct_no_destructor_bad, 0, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::dead_struct_rvalue_ref_bad, 0, DEAD_STORE, [Write of unused value]
-codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::dead_struct_value1_bad, 0, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::dead_then_live_bad, 1, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::easy_bad, 0, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::init_capture_no_call_bad, 1, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::init_capture_reassign_bad, 1, DEAD_STORE, [Write of unused value]
-codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::lambda_bad::lambda_dead_stores.cpp:164:11_operator(), 1, DEAD_STORE, [Write of unused value]
+codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::lambda_bad::lambda_dead_stores.cpp:153:11_operator(), 1, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::plus_plus1_bad, 2, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::plus_plus2_bad, 2, DEAD_STORE, [Write of unused value]
 codetoanalyze/cpp/liveness/dead_stores.cpp, dead_stores::plus_plus3_bad, 2, DEAD_STORE, [Write of unused value]