Info
In #1012, the .classpath file entry forgeSrc is wrong it must be forgeBin.
In #1012, if you run only setupDecompWorkspace eclipse without setupDevWorkspace, it will not build forgeBin jar file.
Instruction
1. Delete ".classspath" file in your forge directory.
2. Run gradlew setupDevWorkspace setupDecompWorkspace eclipse
3. edit the file .classpath
change from
to
4. Run eclipse -data forgedir\eclipse