fix travis

scripts/travis_after_failure.sh

@@ -1,5 +1,5 @@
 #!/bin/bash
 
 if [ ${TASK} == "R-package" ]; then
-    cat R-package/xgboost.Rcheck/*.log
+    cat xgboost/xgboost.Rcheck/*.log
 fi

wrapper/xgboost_wrapper.cpp

@@ -188,7 +188,7 @@ const char *XGBSetGetLastError_(const char *str_set) {
 const char *XGBSetGetLastError_(const char *str_set) {
   return NULL;
 }
-#endif
+#endif  // XGBOOST_STRICT_CXX98_
 
 /*! \brief return str message of the last error */
 const char *XGBGetLastError() {