Translate std::move from system headers to improve analysis quality

Summary:public
Implementation of std::move is straightforward and infer understands it without
any problems. To use it, we translate it even though it's coming from system headers.

Reviewed By: jvillard

Differential Revision: D3064019

fb-gh-sync-id: 823ae75
shipit-source-id: 823ae75

infer/src/clang/cFrontend_decl.ml

@@ -108,6 +108,23 @@ struct
   let process_methods tenv cg cfg curr_class decl_list =
     IList.iter (process_one_method_decl tenv cg cfg curr_class) decl_list
 
+  let should_translate_decl dec =
+    let info = Clang_ast_proj.get_decl_tuple dec in
+    CLocation.update_curr_file info;
+    let source_range = info.Clang_ast_t.di_source_range in
+    let translate_location = CLocation.should_translate_lib source_range in
+    let always_translate_decl = match dec with
+      | Clang_ast_t.FunctionDecl (_, name_info, _, _) ->
+          (* named_decl_info.ni_name has name without template parameters.*)
+          (* It makes it possible to capture whole family of function instantiations*)
+          (* to be named the same *)
+          let fun_name = name_info.Clang_ast_t.ni_name in
+          let top_qual = IList.hd (IList.rev name_info.Clang_ast_t.ni_qual_name) in
+          (* Always translate std::move so that it can be analyzed *)
+          top_qual="std" && fun_name = "move"
+      | _ -> false in
+    translate_location || always_translate_decl
+
   (* Translate one global declaration *)
   let rec translate_one_declaration tenv cg cfg parent_dec dec =
     let open Clang_ast_t in
@@ -115,11 +132,8 @@ struct
     CFrontend_errors.run_frontend_checkers_on_decl tenv cg cfg dec;
     (* each procedure has different scope: start names from id 0 *)
     Ident.NameGenerator.reset ();
-    let info = Clang_ast_proj.get_decl_tuple dec in
+
-    CLocation.update_curr_file info;
+    (if should_translate_decl dec then
-    let source_range = info.Clang_ast_t.di_source_range in
-    let should_translate_decl = CLocation.should_translate_lib source_range in
-    (if should_translate_decl then
        match dec with
        | FunctionDecl(_, _, _, _) ->
            function_decl tenv cfg cg dec None

infer/tests/codetoanalyze/cpp/errors/models/move.cpp

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2016 - 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 <utility>
+
+struct X {
+  X() : f(1) {}
+  X(X&& x) {
+    f = x.f;
+    x.f = 0; // assign zero to field of moved_from object
+  }
+  int f;
+};
+
+int div0_moved_from() {
+  X x1;
+  X x2 = std::move(x1);
+  return 1 / x1.f;
+}
+
+int div1_moved_from() {
+  X x1;
+  X x2 = std::move(x1);
+  return 1 / (x1.f + 1);
+}
+
+int div1_moved_to() {
+  X x1;
+  X x2 = std::move(x1);
+  return 1 / x2.f;
+}
+
+int div0_moved_to() {
+  X x1;
+  X x2 = std::move(x1);
+  return 1 / (x2.f - 1);
+}

infer/tests/codetoanalyze/cpp/errors/smart_ptr/shared_ptr_deref.cpp

@@ -101,3 +101,9 @@ int shared_ptr_assign_ok_deref() {
   p1.reset();
   return *p2;
 }
+
+int shared_ptr_move_null_deref() {
+  std::shared_ptr<int> p1(new int);
+  std::shared_ptr<int> p2 = std::move(p1);
+  return *p1;
+}

infer/tests/endtoend/cpp/MoveModelTest.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2016 - 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.
+ */
+
+package endtoend.cpp;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static utils.matchers.ResultContainsExactly.containsExactly;
+
+
+import com.google.common.collect.ImmutableList;
+
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+import utils.InferResults;
+import utils.InferRunner;
+
+public class MoveModelTest {
+
+  public static final String FILE =
+      "infer/tests/codetoanalyze/cpp/errors/models/move.cpp";
+
+  private static ImmutableList<String> inferCmd;
+
+  public static final String DIVIDE_BY_ZERO = "DIVIDE_BY_ZERO";
+
+  @ClassRule
+  public static DebuggableTemporaryFolder folder =
+      new DebuggableTemporaryFolder();
+
+  @BeforeClass
+  public static void runInfer() throws InterruptedException, IOException {
+    inferCmd = InferRunner.createCPPInferCommand(folder, FILE);
+  }
+
+  @Test
+  public void whenInferRunsOnDiv0FunctionsErrorIsFound()
+      throws InterruptedException, IOException, InferException {
+    String[] procedures = {
+        "div0_moved_from",
+        "div0_moved_to",
+    };
+    InferResults inferResults = InferRunner.runInferCPP(inferCmd);
+    assertThat(
+        "Results should contain divide by 0 error",
+        inferResults,
+        containsExactly(
+            DIVIDE_BY_ZERO,
+            FILE,
+            procedures
+        )
+    );
+  }
+}

infer/tests/endtoend/cpp/SharedPtrDerefTest.java

@@ -57,6 +57,7 @@ public class SharedPtrDerefTest {
         "reset_ptr_null_deref2",
         "shared_ptr_copy_null_deref",
         "shared_ptr_assign_null_deref",
+        "shared_ptr_move_null_deref",
     };
     InferResults inferResults = InferRunner.runInferCPP(inferCmd);
     assertThat(