How can I increase Kotlin Daemon JVM Heap for Kotlin 1.4.20?

Question

I am building a Kotlin 1.4.20 project with Gradle, and I am running out of heap memory during build.

I've tried

kotlinOptions {
  jvmTarget = "1.8"
  freeCompilerArgs += listOf("-Dkotlin.daemon.jvm.options=-Xmx2g")
}

however, this option does not appear to be available in 1.4.20, only 1.5. Are there other ways I can increase the daemon heap memory?

• 1.4.20 https://raw.githubusercontent.com/JetBrains/kotlin/1.4.20/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/Properties.kt
• 1.5.0 https://raw.githubusercontent.com/JetBrains/kotlin/1.5.0/compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/Properties.kt (edited)