[K/N] Disable cms for targets not supporting threads

kotlin-native/backend.native/cli.bc/src/org/jetbrains/kotlin/cli/bc/K2Native.kt

@@ -300,28 +300,17 @@ class K2Native : CLICompiler<K2NativeCompilerArguments>() {
                         DestroyRuntimeMode.ON_SHUTDOWN
                     }
                 })
-                val assertGcSupported = {
-                    if (memoryModel != MemoryModel.EXPERIMENTAL) {
-                        configuration.report(ERROR, "-Xgc is only supported for -memory-model experimental")
-                    }
+                if (arguments.gc != null && memoryModel != MemoryModel.EXPERIMENTAL) {
+                    configuration.report(ERROR, "-Xgc is only supported for -memory-model experimental")
                 }
-                put(GARBAGE_COLLECTOR, when (arguments.gc) {
-                    null -> GC.SAME_THREAD_MARK_AND_SWEEP
-                    "noop" -> {
-                        assertGcSupported()
-                        GC.NOOP
-                    }
-                    "stms" -> {
-                        assertGcSupported()
-                        GC.SAME_THREAD_MARK_AND_SWEEP
-                    }
-                    "cms" -> {
-                        assertGcSupported()
-                        GC.CONCURRENT_MARK_AND_SWEEP
-                    }
+                putIfNotNull(GARBAGE_COLLECTOR, when (arguments.gc) {
+                    null -> null
+                    "noop" -> GC.NOOP
+                    "stms" -> GC.SAME_THREAD_MARK_AND_SWEEP
+                    "cms" -> GC.CONCURRENT_MARK_AND_SWEEP
                     else -> {
                         configuration.report(ERROR, "Unsupported GC ${arguments.gc}")
-                        GC.SAME_THREAD_MARK_AND_SWEEP
+                        null
                     }
                 })
                 if (memoryModel != MemoryModel.EXPERIMENTAL && arguments.gcAggressive) {

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt

@@ -81,7 +81,19 @@ class KonanConfig(val project: Project, val configuration: CompilerConfiguration
         }
     }
     val destroyRuntimeMode: DestroyRuntimeMode get() = configuration.get(KonanConfigKeys.DESTROY_RUNTIME_MODE)!!
-    val gc: GC get() = configuration.get(KonanConfigKeys.GARBAGE_COLLECTOR)!!
+    val gc: GC by lazy {
+        val configGc = configuration.get(KonanConfigKeys.GARBAGE_COLLECTOR)
+        val (gcFallbackReason, realGc) = when {
+            configGc == GC.CONCURRENT_MARK_AND_SWEEP && !target.supportsThreads() ->
+                "Concurrent mark and sweep gc is not supported for this target. Fallback to Same thread mark and sweep is done" to GC.SAME_THREAD_MARK_AND_SWEEP
+            configGc == null -> null to GC.SAME_THREAD_MARK_AND_SWEEP
+            else -> null to configGc
+        }
+        if (gcFallbackReason != null) {
+            configuration.report(CompilerMessageSeverity.STRONG_WARNING, gcFallbackReason)
+        }
+        realGc
+    }
     val gcAggressive: Boolean get() = configuration.get(KonanConfigKeys.GARBAGE_COLLECTOR_AGRESSIVE)!!
     val runtimeAssertsMode: RuntimeAssertsMode get() = configuration.get(BinaryOptions.runtimeAssertionsMode) ?: RuntimeAssertsMode.IGNORE
     val workerExceptionHandling: WorkerExceptionHandling get() = configuration.get(KonanConfigKeys.WORKER_EXCEPTION_HANDLING)!!

kotlin-native/build-tools/src/main/kotlin/org/jetbrains/kotlin/Utils.kt

@@ -386,6 +386,8 @@ fun targetSupportsLibBacktrace(targetName: String) =
 fun targetSupportsCoreSymbolication(targetName: String) =
         HostManager().targetByName(targetName).supportsCoreSymbolication()
 
+fun targetSupportsThreads(targetName: String) =
+        HostManager().targetByName(targetName).supportsThreads()
 
 fun Project.mergeManifestsByTargets(source: File, destination: File) {
     logger.info("Merging manifests: $source -> $destination")

kotlin-native/runtime/build.gradle.kts

@@ -188,6 +188,8 @@ bitcode {
     create("experimental_memory_manager_cms", file("src/mm")) {
         headersDirs += files("src/gc/cms/cpp", "src/gc/common/cpp")
         includeRuntime()
+
+        onlyIf { targetSupportsThreads(target) }
     }
 
     create("common_gc_noop", file("src/gc/common")) {
@@ -203,6 +205,8 @@ bitcode {
     create("common_gc_cms", file("src/gc/common")) {
         headersDirs += files("src/gc/cms/cpp", "src/mm/cpp")
         includeRuntime()
+
+        onlyIf { targetSupportsThreads(target) }
     }
 
     create("noop_gc", file("src/gc/noop")) {
@@ -218,6 +222,8 @@ bitcode {
     create("concurrent_ms_gc", file("src/gc/cms")) {
         headersDirs += files("src/gc/cms/cpp", "src/gc/common/cpp", "src/mm/cpp")
         includeRuntime()
+
+        onlyIf { targetSupportsThreads(target) }
     }
 }