KT-46820: Kotlin gradle plugin - prevent multiple threads from registering task

... as that is not supported by the underlying mechanism.
Build service that holds info about the incremnetal compilation
may be instantiated only during execution, and multiple tasks may
try to do that. Because the container which holds info about all
build services is not thread-safe, this change adds synchronization.

Fixes #KT-46820

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

@@ -120,10 +120,17 @@ class GradleCompileTaskProvider(task: Task) {
     val projectName: String = task.project.rootProject.name.normalizeForFlagFile()
     val buildModulesInfo: Provider<out IncrementalModuleInfoProvider> = run {
         val modulesInfo = GradleCompilerRunner.buildModulesInfo(task.project.gradle)
-        task.project.gradle.sharedServices.registerIfAbsent(
-            IncrementalModuleInfoBuildService.getServiceName(), IncrementalModuleInfoBuildService::class.java
-        ) {
-            it.parameters.info.set(modulesInfo)
+        /**
+         * See https://youtrack.jetbrains.com/issue/KT-46820. Build service that holds the incremental info may
+         * be instantiated during execution phase and there could be multiple threads trying to do that. Because the
+         * underlying mechanism does not support multi-threaded access, we need to add external synchronization.
+         */
+        synchronized(task.project.gradle.sharedServices) {
+            task.project.gradle.sharedServices.registerIfAbsent(
+                IncrementalModuleInfoBuildService.getServiceName(), IncrementalModuleInfoBuildService::class.java
+            ) {
+                it.parameters.info.set(modulesInfo)
+            }
         }
     }
 }