Upgraded to IntelliJ IDEA 2018.2 and now I get this error message every time on runtime:
objc: Class JavaLaunchHelper is implemented in both /Library/Java/JavaVirtualMachines/jdk1.8.0_40.jdk/Contents/Home/bin/java (0x1060fe4c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_40.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x10618a4e0). One of the two will be used. Which one is undefined.
I did not have this error with previous version of IntelliJ IDEA, using the same jdk.