/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.2 failed with exit code 1 error [duplicate]

Answer 1

I had this same problem when i add Reliability class to my code. I already included tree20 to my project which is having reliability class. So when I add the reliability class again to my class I got the same error. I removed the Reliability code from my project and it works perfect.

Answer 2

It means the MainView class is defined twice or more.

Check:

1. If the MainView class's @implementation appears in any .h files. It shouldn't.
2. If there are 2 MainView classes define by you and a third-party library. You may need to rename your MainView class.

Answer 3

As KennyTM is correct.

I accidentally imported the .m file instead of the .h an received this lovely error.