Disable USE_CYCLIC_GC (#4142)

backend.native/tests/build.gradle

@@ -1019,7 +1019,7 @@ task atomic0(type: KonanLocalTest) {
 
 standaloneTest("atomic1") {
     // Note: This test reproduces a race, so it'll start flaking if problem is reintroduced.
-    enabled = (project.testTarget != 'wasm32') // Workers need pthreads.
+    enabled = false // Needs USE_CYCLIC_GC, which is disabled.
     source = "runtime/workers/atomic1.kt"
 }
 
@@ -2793,12 +2793,13 @@ task memory_stable_ref_cross_thread_check(type: KonanLocalTest) {
 }
 
 standaloneTest("cycle_collector") {
-    disabled = project.globalTestArgs.contains('-opt') || (project.testTarget == 'wasm32') // Needs debug build.
+    disabled = true // Needs USE_CYCLIC_GC, which is disabled.
     flags = ['-g']
     source = "runtime/memory/cycle_collector.kt"
 }
 
 standaloneTest("cycle_collector_deadlock1") {
+    disabled = true // Needs USE_CYCLIC_GC, which is disabled.
     source = "runtime/memory/cycle_collector_deadlock1.kt"
 }
 

runtime/src/main/cpp/Memory.cpp

@@ -20,7 +20,7 @@
 #include <cstddef> // for offsetof
 
 // Allow concurrent global cycle collector.
-#define USE_CYCLIC_GC 1
+#define USE_CYCLIC_GC 0
 
 #include "Alloc.h"
 #include "KAssert.h"