From 0425826fe89e0ad3111aee6cc352ad24d8c38525 Mon Sep 17 00:00:00 2001
From: Nikolay Igotti <olonho@users.noreply.github.com>
Date: Mon, 17 Feb 2020 13:45:09 +0300
Subject: [PATCH] Fix GC deinit race leading to bogus leak reports. (#3865)

---
 runtime/src/main/cpp/CyclicCollector.cpp |  2 +-
 runtime/src/main/cpp/Memory.cpp          | 12 ++++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/runtime/src/main/cpp/CyclicCollector.cpp b/runtime/src/main/cpp/CyclicCollector.cpp
index d2b27add5f2..d7f12009b65 100644
--- a/runtime/src/main/cpp/CyclicCollector.cpp
+++ b/runtime/src/main/cpp/CyclicCollector.cpp
@@ -169,7 +169,7 @@ class CyclicCollector {
          restartCount = 0;
         restart:
          COLLECTOR_LOG("start cycle GC\n");
-         if (restartCount > 10) {
+         if (restartCount > 10 && !terminateCollector_) {
            COLLECTOR_LOG("wait for some time to avoid GC trashing\n");
            struct timeval tv;
            struct timespec ts;
diff --git a/runtime/src/main/cpp/Memory.cpp b/runtime/src/main/cpp/Memory.cpp
index e9435d98aae..9375fe1fb5c 100644
--- a/runtime/src/main/cpp/Memory.cpp
+++ b/runtime/src/main/cpp/Memory.cpp
@@ -1748,11 +1748,18 @@ MemoryState* initMemory() {
 }
 
 void deinitMemory(MemoryState* memoryState) {
+  static int pendingDeinit = 0;
+  atomicAdd(&pendingDeinit, 1);
 #if USE_GC
   bool lastMemoryState = atomicAdd(&aliveMemoryStatesCount, -1) == 0;
+  bool checkLeaks = g_checkLeaks && lastMemoryState;
   if (lastMemoryState) {
    garbageCollect(memoryState, true);
 #if USE_CYCLIC_GC
+   // If there are other pending deinits (rare situation) - just skip the leak checker.
+   if (atomicGet(&pendingDeinit) > 1) {
+     checkLeaks = false;
+   }
    cyclicDeinit();
 #endif  // USE_CYCLIC_GC
   }
@@ -1770,9 +1777,10 @@ void deinitMemory(MemoryState* memoryState) {
   konanDestructInstance(memoryState->tlsMap);
   RuntimeAssert(memoryState->finalizerQueue == nullptr, "Finalizer queue must be empty");
   RuntimeAssert(memoryState->finalizerQueueSize == 0, "Finalizer queue must be empty");
-
 #endif // USE_GC
 
+  atomicAdd(&pendingDeinit, -1);
+
 #if TRACE_MEMORY
   if (IsStrictMemoryModel && lastMemoryState && allocCount > 0) {
     MEMORY_LOG("*** Memory leaks, leaked %d containers ***\n", allocCount);
@@ -1780,7 +1788,7 @@ void deinitMemory(MemoryState* memoryState) {
   }
 #else
 #if USE_GC
-  if (IsStrictMemoryModel && lastMemoryState && allocCount > 0 && g_checkLeaks) {
+  if (IsStrictMemoryModel && allocCount > 0 && checkLeaks) {
     char buf[1024];
     konan::snprintf(buf, sizeof(buf),
         "Memory leaks detected, %d objects leaked!\n"