A couple thoughts...
I teach my students to right-click on the project they want to build (in the left pane) and select "Build Project" ... this way there's no question what was being asked of Eclipse.
I would suggest doing the following to help further diagnose if the above doesn't help (which it probably wont since its really just general)...
- Right click on the project and select 'clean project'
- Verify it's clean by opening up the 'Debug' folder in eclipse for that project and you should NOT see FRCUserProgram which is the final binary output file that gets sent to the roborRIO
- Click on the 'problems' tab in the lower / console area at the bottom of Eclipse.
- Right click on 'Errors' and select 'Delete' - and confirm.
- Right click on 'Warnings' and select 'Delete' - and confirm.
- Confirm there is nothing in the 'problems' tab any longer. This is a bit painful but will make sure you're only looking at NEW problems and not old ones.
- Now right click on the project again and select 'Build Project' ...
After it completes, look in the 'problems' tab for errors and warnings.
- If there are errors/warnings - post them here.
- If there are no errors, take a look again in the Debug folder in the project (left pane) and see if there is a FRCUserProgram (this would indicate a successful compile)
- If there is indeed an FRCUserProgram, then you should be good to right click on the project and select RunAs->WPILibC++Deploy
If you got to the deploy - then check in the lower area for a 'Console' tab which will have the results of the deploy operation.
Once this works well, it shouldn't be so painful as described above. I'm just trying to eliminate any variables I can so that the next step of troubleshooting becomes illuminating of the root cause. Hopefully.
bob