Correct specialization of throw_on_error for pointer types

paddle/platform/enforce.h

@@ -127,9 +127,15 @@ inline typename std::enable_if<sizeof...(Args) != 0, void>::type throw_on_error(
 
 #endif  // PADDLE_ONLY_CPU
 
-template <typename T>
-inline void throw_on_error(T* e) {
-  throw_on_error(e != nullptr, "");
+template <typename T, typename... Args>
+inline typename std::enable_if<std::is_pointer<T>::value, void>::type
+throw_on_error(T stat, const Args&... args) {
+  if (stat == nullptr) {
+    return;
+  } else {
+    throw std::runtime_error("Pointer value is nullptr: " +
+                             string::Sprintf(args...));
+  }
 }
 
 template <typename T>