Class 'kotlin.Unit' was compiled with an incompatible version of Kotlin #457
Description
I have a working Android project (that is, ./gradlew build builds an apk file that can be installed and run) which is written in Kotlin. When I open the project in Emacs with LSP using kotlin-language-server, I receive the following diagnostic on every line of code:
Class 'kotlin.Unit' was compiled with an incompatible version of Kotlin. The binary version of its metadata is 1.8.0, expected version is 1.6.0. The class is loaded from /home/raxod502/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.8.20/e72fc5e03ec6c064c678a6bd0d955c88d55b0c4a/kotlin-stdlib-1.8.20.jar!/kotlin/Unit.class I checked Editor integration and Troubleshooting but did not see any relevant tips. I also searched the issue tracker but found only #198 (comment) as a reference, which doesn't seem relevant in this case.
Here's my build.gradle.kts:
plugins { id("com.android.application") version "7.4.2" id("org.jetbrains.kotlin.android") version "1.8.20" } repositories { google() mavenCentral() } android { compileSdkVersion(32) namespace = "redacted" defaultConfig { applicationId = "redacted" minSdkVersion(16) targetSdkVersion(32) versionCode = 1 versionName = "0.1.0" } buildTypes { getByName("release") { isMinifyEnabled = false } } compileOptions { sourceCompatibility = JavaVersion.VERSION_17 targetCompatibility = JavaVersion.VERSION_17 } } dependencies { implementation("androidx.appcompat:appcompat:1.2.0") implementation("com.google.android.material:material:1.2.0") implementation("androidx.constraintlayout:constraintlayout:2.0.4") } I don't, to my knowledge, have Kotlin installed globally on my system. The only place it's installed is via Gradle in this project, where the version is specified in build.gradle.kts as 1.8.20. I am not sure where this other 1.6.0 version number is coming from that is being referenced by kotlin-language-server.
If it would help in diagnosing the issue, I am happy to provide a sample project that reproduces the issue, or relevant logs.