performing cleanup (and memory usage reporting) only if kotlin compiler was actually called, should fix e.g. KT-10127

libraries/tools/kotlin-gradle-plugin-core/src/main/kotlin/org/jetbrains/kotlin/gradle/tasks/Tasks.kt

@@ -42,6 +42,7 @@ abstract class AbstractKotlinCompile<T : CommonCompilerArguments>() : AbstractCo
 
     public var kotlinOptions: T = createBlankArgs()
     public var kotlinDestinationDir: File? = destinationDir
+    var compilerCalled: Boolean = false
 
     private val loggerInstance = Logging.getLogger(this.javaClass)
     override fun getLogger() = loggerInstance
@@ -56,6 +57,7 @@ abstract class AbstractKotlinCompile<T : CommonCompilerArguments>() : AbstractCo
             return
         }
 
+        compilerCalled = true
         populateCommonArgs(args, sources)
         populateTargetSpecificArgs(args)
         callCompiler(args)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/CleanUpBuildListener.kt

@@ -19,7 +19,9 @@ package org.jetbrains.kotlin.gradle.plugin
 import org.apache.commons.lang.SystemUtils
 import org.gradle.BuildAdapter
 import org.gradle.BuildResult
+import org.gradle.api.Project
 import org.gradle.api.logging.Logging
+import org.gradle.api.tasks.compile.AbstractCompile
 import java.util.concurrent.ScheduledExecutorService
 import kotlin.properties.Delegates
 
@@ -34,7 +36,7 @@ private fun comparableVersionStr(version: String) =
                 ?.let { if (it.all { (it?.value?.length ?: 0).let { it > 0 && it < 4 }}) it else null }
                 ?.joinToString(".", transform = { it!!.value.padStart(3, '0') })
 
-class CleanUpBuildListener(pluginClassLoader: ClassLoader) : BuildAdapter() {
+class CleanUpBuildListener(pluginClassLoader: ClassLoader, private val project: Project) : BuildAdapter() {
     companion object {
         const val FORCE_SYSTEM_GC_MESSAGE = "Forcing System.gc()"
     }
@@ -53,23 +55,35 @@ class CleanUpBuildListener(pluginClassLoader: ClassLoader) : BuildAdapter() {
     }
 
     override fun buildFinished(result: BuildResult?) {
-        log.kotlinDebug("Build finished listener")
-
         val gradle = result?.gradle
         if (gradle != null) {
-            cleanup(gradle.gradleVersion)
-            // checking thread leaks only then cleaning up
-            threadTracker?.checkThreadLeak(gradle)
+
+            val kotlinCompilerCalled = project.tasks.filter { it.name.contains("kotlin", ignoreCase = true) }
+                    .any { task -> task.hasProperty("compilerCalled") && task.property("compilerCalled") as? Boolean ?: false }
+
+            if (kotlinCompilerCalled) {
+                log.kotlinDebug("Cleanup after kotlin")
+
+                cleanup(gradle.gradleVersion)
+
+                // checking thread leaks only then cleaning up
+                threadTracker?.checkThreadLeak(gradle)
+            }
+            else {
+                log.kotlinDebug("Skipping kotlin cleanup since compiler wasn't called")
+            }
 
             threadTracker = null
             gradle.removeListener(this)
-        }
 
-        startMemory?.let { startMemoryCopy ->
-            getUsedMemoryKb()?.let { endMemory ->
-                // the value reported here is not necessarily a leak, since it is calculated before collecting the plugin classes
-                // but on subsequent runs in the daemon it should be rather small, then the classes are actually reused by the daemon (see above)
-                log.kotlinDebug("[PERF] Used memory after build: $endMemory kb (difference since build start: ${"%+d".format(endMemory - startMemoryCopy)} kb)")
+            if (kotlinCompilerCalled) {
+                startMemory?.let { startMemoryCopy ->
+                    getUsedMemoryKb()?.let { endMemory ->
+                        // the value reported here is not necessarily a leak, since it is calculated before collecting the plugin classes
+                        // but on subsequent runs in the daemon it should be rather small, then the classes are actually reused by the daemon (see above)
+                        log.kotlinDebug("[PERF] Used memory after build: $endMemory kb (difference since build start: ${"%+d".format(endMemory - startMemoryCopy)} kb)")
+                    }
+                }
             }
         }
     }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPluginWrapper.kt

@@ -14,10 +14,6 @@ abstract class KotlinBasePluginWrapper: Plugin<Project> {
     val log = Logging.getLogger(this.javaClass)
 
     override fun apply(project: Project) {
-        val cleanUpBuildListener = CleanUpBuildListener(this.javaClass.classLoader)
-        cleanUpBuildListener.buildStarted()
-        project.gradle.addBuildListener(cleanUpBuildListener)
-
         val sourceBuildScript = findSourceBuildScript(project)
         if (sourceBuildScript == null) {
             log.error("Failed to determine source cofiguration of kotlin plugin. Can not download core. Please verify that this or any parent project " +
@@ -31,6 +27,9 @@ abstract class KotlinBasePluginWrapper: Plugin<Project> {
         val plugin = getPlugin(this.javaClass.classLoader, sourceBuildScript)
         plugin.apply(project)
 
+        val cleanUpBuildListener = CleanUpBuildListener(this.javaClass.classLoader, project)
+        cleanUpBuildListener.buildStarted()
+        project.gradle.addBuildListener(cleanUpBuildListener)
     }
 
     protected abstract fun getPlugin(pluginClassLoader: ClassLoader, scriptHandler: ScriptHandler): Plugin<Project>