Cannot inline bytecode built with JVM target 1.8 into bytecode that is being built with JVM target 1.6

Question

When trying to run the Example CorDapp (GitHub CorDapp) via IntelliJ, I receive the following error:

Cannot inline bytecode built with JVM target 1.8 int

Answer 1

in most cases this is enough:

compileKotlin {
    kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}

if you have declared custom Gradle tasks like integrationTest for example, add a configuration for compileKotlin as well:

compileIntegrationTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}