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kotlinlang

I'm trying to build kotlin per its instructions, but it seems to require environment variables for 4 Java versions. Why is this?

And please do not cross-post in multiple channels. Pick one that is appropriate and stick with it or at most post a link in other channels or you wast everyone's time that need to read your message multiple times and split discussions.

<#C0BUHC9HD|kontributors> is more appropriate channel for it

As for original question, so they are needed for building kotlin-stdlib for different target JDK's (e.g. there are some specific functions in stdlib which use classes from JDK8) and for testing purposes (e.g. compile tests using compiler which ran in java 8 process and then run compiled code in java 6 process)