我在自定義話題消息的時候編譯出錯：
CMake Error at /home/sophie/ghl/catkin_ghl/build/learning_communication/cmake/learning_communication-genmsg.cmake:3 (message):
Could not find messages which
'/home/sophie/ghl/catkin_ghl/src/learning_communication/msg/Person.msg'
depends on. Did you forget to specify generate_messages(DEPENDENCIES ...)?
Cannot locate message [String] in package [learning_communication] with
paths [['/home/sophie/ghl/catkin_ghl/src/learning_communication/msg']]
Call Stack (most recent call first):
/opt/ros/kinetic/share/genmsg/cmake/genmsg-extras.cmake:307 (include)
learning_communication/CMakeLists.txt:71 (generate_messages)
-- Configuring incomplete, errors occurred!
See also "/home/sophie/ghl/catkin_ghl/build/CMakeFiles/CMakeOutput.log".
See also "/home/sophie/ghl/catkin_ghl/build/CMakeFiles/CMakeError.log".
Makefile:556: recipe for target 'cmake_check_build_system' failed
make: *** [cmake_check_build_system] Error 1
Invoking "make cmake_check_build_system" failed
原因：我的Person.msg文件內容寫錯了。
string name // 之前寫成String了，s大寫了，所以一直編譯報錯
uint8 sex
uint8 age
uint8 unknown = 0
uint8 male = 1
uint8 female = 2
一定要細心啊！