How do you use external Scala compiler with IDEA 12?

Question

How do you use external Scala compiler with IDEA ? I seem to have randomly appearing errors saying "scala: Cannot connect to compile server at localhost/127.0.0.1:3200"

Sometimes it works. Sometimes it doesn't. I can't find the pattern.

Here is what I have in the log

9:20:58 PM Auto make completed with errors
9:21:09 PM Using a new (SBT-based) Scala compiler.
           In case of any compilation problems you may enable the previous (internal) compiler by clearing:
           Project Settings / Compiler / Use external build
9:21:10 PM Scala compile server
           Error: Could not create the Java Virtual Machine.
           Error: A fatal exception has occurred. Program will exit.

9:21:12 PM Compilation completed with 1 error and 0 warnings in 3 sec

I'm using

• IDEA 12.1 (129.161)
• Scala compiler 2.10.1
• Scala plugin 0.7.213
• JDK 1.7
• Windows 7

In Project Settings / Compiler / Use external build is checked. In IDE Settings / Scala / Run compile server is checked.

Do I need to launch compiler server manually ? Anything else ?

UPD: Looks like bug to me. I posted JIRA ticket http://youtrack.jetbrains.com/issue/SCL-5523

Answer 1

You need to lower the heap size from 1024 to 512 or something. Then the compile server can be created and started. Tried with the InteliJ 13.0.2 (133.331) and Scala plugin 0.26.361

Answer 2

Go to Settings -> Compiler and uncheck "Use external build"