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kotlinlang

When I switched a project over to Java 11 (from 8 ) and converted to Gradle Kotlin DSL, I suddenly got a bunch of red underlines... I checked project structure dialog, couldn't find anything not 11...

How do I configure gradle to get rid of all the red? The project actually compiles as-is...

I had something similar: <https://youtrack.jetbrains.com/issue/KTIJ-815>

Check that you also have "File | Settings | Build, Execution, Deployment | Build Tools | Gradle | JVM" = Project SDK. Also might help: remove (rename) config and system IDEA directories (<https://www.jetbrains.com/help/idea/tuning-the-ide.html#config-directory>), remove cache from `~/.gradle`, remove .idea project directory and reimport the project.

Nope <@UB3CEA8QG>... still all red, maybe I played around with my build script too much... I currently have this:
```tasks {
    withType&lt;KotlinCompile&gt;().configureEach {
        sourceCompatibility = JavaVersion.VERSION_11.toString()
        targetCompatibility = JavaVersion.VERSION_11.toString()

        kotlinOptions {
            jvmTarget = JavaVersion.VERSION_11.toString()
            useIR = true
        }

    }
}```

Ok, last time I had to invalidate caches/restart, and then after a very long time of rebuilding all caches, it worked after that setting <@UB3CEA8QG>, but when I got to work today, the settings were back to their old values... and the red is back :face_with_thermometer:. Is there anything shorter to do than invalidate cache/restart?

~I had to restart the IDE after changing the settings and erasing the `.idea/` folder, only then it gave me the option to re-import the project~ :cry:~, it took less time than invalidating caches, but why doesn't it ask me when the files were erased?~

~It goes back to java 8 after erasing the `.idea/` folder and re-importing... that's why it works. But it seems I can't change it to java 11.~

Ok, it was trying to use the jvm of intellij's snap for 11... and that  didn't seem to work.