Adding platform/must_check.h

__must_check is a macro mark of function return value. It let developer
must check the return value is legal or not.

paddle/platform/CMakeLists.txt

@@ -2,3 +2,4 @@ nv_test(cuda_test SRCS cuda_test.cu)
 
 cc_library(place SRCS place.cc)
 cc_test(place_test SRCS place_test.cc DEPS place glog gflags)
+cc_test(must_check_test SRCS must_check_test.cc)

paddle/utils/Compiler.h → paddle/platform/must_check.h

@@ -10,24 +10,17 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 
 #pragma once
-/**
- * This header defines some useful attribute by each compiler. It is the
- * abstract layer of compilers.
- */
-#ifdef __GNUC__
-#define GCC_VERSION \
-  (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__)
-#else
-#define GCC_VERSION
-#endif
-
 /**
  * __must_check macro. It make the function's return value must be used,
  * otherwise it will raise a compile warning. And also Paddle treat all compile
  * warnings as errors.
  */
-#if GCC_VERSION >= 30400
+#ifdef __GNUC__
+#if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >= 30400
 #define __must_check __attribute__((warn_unused_result))
 #else
 #define __must_check
 #endif
+#else
+#define __must_check
+#endif

paddle/platform/must_check_test.cc

+#include <gtest/gtest.h>
+#include <paddle/platform/must_check.h>
+
+int __must_check SomeFunctionMustCheck() { return 0; }
+
+TEST(MustCheck, all) {
+  //  This line should not be compiled, because the
+  //  return value of SomeFunctionMustCheck marked as __must_check
+  //  SomeFunctionMustCheck();
+}
\ No newline at end of file

paddle/utils/Error.h

@@ -19,7 +19,7 @@ limitations under the License. */
 #include <stdio.h>
 #include <memory>
 #include <string>
-#include "Compiler.h"
+#include "paddle/platform/must_check.h"
 
 namespace paddle {