Make tensorflow::Status TF_MUST_USE_RESULT, and alias xla::Status to tensorflow::Status.

To make this work, we have to add a few IgnoreError() calls to
TensorFlow.
Change: 150080076

tensorflow/compiler/xla/status.h

@@ -21,29 +21,7 @@ limitations under the License.
 
 namespace xla {
 
-#if defined(__clang__)
-// Only clang supports warn_unused_result as a type annotation.
-class TF_MUST_USE_RESULT Status;
-#endif
-
-// Simple wrapper around tensorflow::Status that has the MUST_USE_RESULT
-// annotation above. When tensorflow::Status adopts this annotation, this can
-// simply become a "using tensorflow::Status".
-class Status : public tensorflow::Status {
- public:
-  static Status OK() { return tensorflow::Status::OK(); }
-
-  // Note: implicit constructor.
-  Status(tensorflow::Status other) : tensorflow::Status(other) {}
-
-  Status() : tensorflow::Status() {}
-  Status(tensorflow::error::Code code, tensorflow::StringPiece msg)
-      : tensorflow::Status(code, msg) {}
-
-  // Ignores any errors. This method is a nop that can be used to suppress
-  // compiler errors when a Status value is intentially ignored.
-  void IgnoreError() const {}
-};
+using tensorflow::Status;
 
 }  // namespace xla
 

tensorflow/compiler/xla/statusor.h

@@ -105,7 +105,6 @@ class StatusOr {
   // In optimized builds, passing Status::OK here will have the effect
   // of passing tensorflow::error::INTERNAL as a fallback.
   StatusOr(Status status);              // NOLINT
-  StatusOr(tensorflow::Status status);  // NOLINT
 
   // Construct a new StatusOr with the given value. If T is a plain pointer,
   // value must not be NULL. After calling this constructor, calls to
@@ -196,8 +195,6 @@ class StatusOr<T, false> : public StatusOr<T, true> {
       : StatusOr<T, true>::StatusOr(std::move(value)) {}
   StatusOr(Status status)  // NOLINT
       : StatusOr<T, true>::StatusOr(std::move(status)) {}
-  StatusOr(tensorflow::Status status)  // NOLINT
-      : StatusOr<T, true>::StatusOr(std::move(status)) {}
   template <typename U>
   StatusOr(StatusOr<U>&& other)  // NOLINT
       : StatusOr<T, true>::StatusOr(std::move(other)) {}
@@ -245,14 +242,6 @@ inline StatusOr<T, CopyConstructible>::StatusOr(Status status)
   }
 }
 
-template <typename T, bool CopyConstructible>
-inline StatusOr<T, CopyConstructible>::StatusOr(tensorflow::Status status)
-    : status_(status) {
-  if (status_.ok()) {
-    status_ = internal::StatusOrHelper::HandleInvalidStatusCtorArg();
-  }
-}
-
 template <typename T, bool CopyConstructible>
 inline StatusOr<T, CopyConstructible>::StatusOr(const T& value)
     : value_(value) {

tensorflow/core/lib/core/status.h

@@ -22,9 +22,15 @@ limitations under the License.
 #include "tensorflow/core/lib/core/error_codes.pb.h"
 #include "tensorflow/core/lib/core/stringpiece.h"
 #include "tensorflow/core/platform/logging.h"
+#include "tensorflow/core/platform/macros.h"
 
 namespace tensorflow {
 
+#if defined(__clang__)
+// Only clang supports warn_unused_result as a type annotation.
+class TF_MUST_USE_RESULT Status;
+#endif
+
 /// @ingroup core
 /// Denotes success or failure of a call in Tensorflow.
 class Status {