outroot@cass:~/projects$ revel package testapp
~
~ revel! http://robfig.github.com/revel
~
2012/10/18 19:23:55 run.go:125: Exec: [/home/outroot/dev/go/bin/go build -o /home/outroot/projects/bin/testapp testapp/app/tmp]
Abort: Failed to create directory: mkdir /tmp/testapp794838921/testapp: not a directory
outroot@cass:~/projects$ ls /tmp
testapp794838921
outroot@cass:~/projects$ ls /tmp/testapp794838921/
testapp github.com
outroot@cass:~/projects$ file /tmp/testapp794838921/testapp
/tmp/testapp794838921/testapp: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), not stripped
So it seems it's trying to create a directory on the ELF executable file.