我无法使用roscore。前段时间还能正常工作，但现在已经不能工作了，我已经卸载并重新安装了2次ros melodic，但没有用。我已经卸载并重新安装了2次ros melodic，但都没有用，这是我运行roscore时的情况。
aditya@aditya-Lenovo-ideapad-300-15ISK:~/catkin_ws$ roscore
... logging to /home/aditya/.ros/log/781e2678-995e-11ea-a38d-e0946779fe64/roslaunch-aditya-Lenovo-ideapad-300-15ISK-5956.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://aditya-Lenovo-ideapad-300-15ISK:46667/
ros_comm version 1.13.0
SUMMARY
========
PARAMETERS
* /rosdistro: melodic
* /rosversion: 1.13.0
NODES
auto-starting new master
process[master]: started with pid [5967]
ROS_MASTER_URI=http://aditya-Lenovo-ideapad-300-15ISK:11311/
setting /run_id to 781e2678-995e-11ea-a38d-e0946779fe64
ERROR: rosout is not built. Please run 'rosmake rosout'
failed to start core service [/rosout]
The traceback for the exception was written to the log file
[master] killing on exit
当我运行rosmake rosout:rosmake rosout时...
[ rosmake ] rosmake starting...
[ rosmake ] Packages requested are: ['rosout']
[ rosmake ] Logging to directory /home/aditya/.ros/rosmake/rosmake_output-20200519-045259
[ rosmake ] Expanded args ['rosout'] to:
['rosout']
[rosmake-0] Starting >>> catkin [ make ]
[rosmake-0] Finished <<< catkin ROS_NOBUILD in package catkin
No Makefile in package catkin
[rosmake-0] Starting >>> genmsg [ make ]
[rosmake-0] Finished <<< genmsg ROS_NOBUILD in package genmsg
No Makefile in package genmsg
[rosmake-0] Starting >>> genlisp [ make ]
[rosmake-1] Starting >>> genpy [ make ]
[rosmake-3] Starting >>> gencpp [ make ]
[rosmake-0] Finished <<< genlisp ROS_NOBUILD in package genlisp
No Makefile in package genlisp
[rosmake-2] Starting >>> geneus [ make ]
[rosmake-0] Starting >>> gennodejs [ make ]
[rosmake-2] Finished <<< geneus ROS_NOBUILD in package geneus
No Makefile in package geneus
[rosmake-2] Starting >>> cpp_common [ make ]
[rosmake-3] Finished <<< gencpp ROS_NOBUILD in package gencpp
No Makefile in package gencpp
[rosmake-3] Starting >>> ros_environment [ make ]
[rosmake-1] Finished <<< genpy ROS_NOBUILD in package genpy
No Makefile in package genpy
[rosmake-1] Starting >>> cmake_modules [ make ]
[rosmake-2] Finished <<< cpp_common ROS_NOBUILD in package cpp_common
No Makefile in package cpp_common
[rosmake-0] Finished <<< gennodejs ROS_NOBUILD in package gennodejs
No Makefile in package gennodejs
[rosmake-2] Starting >>> rostime [ make ]
[rosmake-0] Starting >>> message_generation [ make ]
[rosmake-1] Finished <<< cmake_modules ROS_NOBUILD in package cmake_modules
No Makefile in package cmake_modules
[rosmake-3] Finished <<< ros_environment ROS_NOBUILD in package ros_environment
No Makefile in package ros_environment
[rosmake-3] Starting >>> rosmake [ make ]
[rosmake-1] Starting >>> rospack [ make ]
[rosmake-2] Finished <<< rostime ROS_NOBUILD in package rostime
No Makefile in package rostime
[rosmake-2] Starting >>> roscpp_traits [ make ]
[rosmake-0] Finished <<< message_generation ROS_NOBUILD in package message_generation
No Makefile in package message_generation
[rosmake-0] Starting >>> roslang [ make ]
[rosmake-1] Finished <<< rospack ROS_NOBUILD in package rospack
No Makefile in package rospack
[rosmake-1] Starting >>> xmlrpcpp [ make ]
[rosmake-2] Finished <<< roscpp_traits ROS_NOBUILD in package roscpp_traits
No Makefile in package roscpp_traits
[rosmake-3] Finished <<< rosmake ROS_NOBUILD in package rosmake
No Makefile in package rosmake
[rosmake-2] Starting >>> roscpp_serialization [ make ]
[rosmake-3] Starting >>> roslib [ make ]
[rosmake-0] Finished <<< roslang ROS_NOBUILD in package roslang
No Makefile in package roslang
[rosmake-2] Finished <<< roscpp_serialization ROS_NOBUILD in package roscpp_serialization
No Makefile in package roscpp_serialization
[rosmake-2] Starting >>> message_runtime [ make ]
[rosmake-1] Finished <<< xmlrpcpp ROS_NOBUILD in package xmlrpcpp
No Makefile in package xmlrpcpp
[rosmake-3] Finished <<< roslib ROS_NOBUILD in package roslib
No Makefile in package roslib
[rosmake-3] Starting >>> rosunit [ make ]
[rosmake-2] Finished <<< message_runtime ROS_NOBUILD in package message_runtime
No Makefile in package message_runtime
[rosmake-2] Starting >>> std_msgs [ make ]
[rosmake-0] Starting >>> rosbuild [ make ]
[rosmake-3] Finished <<< rosunit ROS_NOBUILD in package rosunit
No Makefile in package rosunit
[rosmake-2] Finished <<< std_msgs ROS_NOBUILD in package std_msgs
No Makefile in package std_msgs
[rosmake-2] Starting >>> rosgraph_msgs [ make ]
[rosmake-0] Finished <<< rosbuild ROS_NOBUILD in package rosbuild
No Makefile in package rosbuild
[rosmake-0] Starting >>> rosconsole [ make ]
[rosmake-2] Finished <<< rosgraph_msgs ROS_NOBUILD in package rosgraph_msgs
No Makefile in package rosgraph_msgs
[rosmake-0] Finished <<< rosconsole ROS_NOBUILD in package rosconsole
No Makefile in package rosconsole
[rosmake-3] Starting >>> roscpp [ make ]
[rosmake-3] Finished <<< roscpp ROS_NOBUILD in package roscpp
No Makefile in package roscpp
[rosmake-3] Starting >>> rosout [ make ]
[rosmake-3] Finished <<< rosout ROS_NOBUILD in package rosout
No Makefile in package rosout
[ rosmake ] Results:
[ rosmake ] Built 27 packages with 0 failures.
[ rosmake ] Summary output to directory
[ rosmake ] /home/aditya/.ros/rosmake/rosmake_output-20200519-045259
请帮助我，我有一个项目即将提交。
我是ros的新手，所以我没有意识到这一点。问题出在我的catkin工作区里，所以我删除了它，并创建了一个新的工作区，这就解决了问题。
... logging to /home/aditya/.ros/log/9112b5e4-99d7-11ea-b44d-e0946779fe64/roslaunch-aditya-Lenovo-ideapad-300-15ISK-13672.log
Checking log directory for disk usage. This may take a while.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.
started roslaunch server http://aditya-Lenovo-ideapad-300-15ISK:37647/
ros_comm version 1.14.5
SUMMARY
========
PARAMETERS
* /rosdistro: melodic
* /rosversion: 1.14.5
NODES
auto-starting new master
process[master]: started with pid [13682]
ROS_MASTER_URI=http://aditya-Lenovo-ideapad-300-15ISK:11311/
setting /run_id to 9112b5e4-99d7-11ea-b44d-e0946779fe64
process[rosout-1]: started with pid [13693]
started core service [/rosout]
^C[rosout-1] killing on exit
[master] killing on exit
shutting down processing monitor...
... shutting down processing monitor complete
done
非常感谢@MRFalcon的回复！这个问题是由于我安装了一个插件而发生的，因此，我复制了我所有的包，除了插件，运行了 catkin_make，然后 roscore.这为我解决了问题。