diff --git a/src/libipc/waiter_helper.h b/src/libipc/waiter_helper.h
index a366461..4493306 100644
--- a/src/libipc/waiter_helper.h
+++ b/src/libipc/waiter_helper.h
@@ -34,7 +34,6 @@ struct waiter_helper {
         counter.waiting_.fetch_add(1, std::memory_order_release);
         flags.is_waiting_.store(true, std::memory_order_relaxed);
         auto finally = ipc::guard([&ctrl, &counter, &flags] {
-            ctrl.get_lock(); // barrier
             for (auto curr_wait = counter.waiting_.load(std::memory_order_relaxed); curr_wait > 0;) {
                 if (counter.waiting_.compare_exchange_weak(curr_wait, curr_wait - 1, std::memory_order_acq_rel)) {
                     break;
diff --git a/test/test_ipc.cpp b/test/test_ipc.cpp
index 428cbd1..79f3b26 100755
--- a/test/test_ipc.cpp
+++ b/test/test_ipc.cpp
@@ -18,8 +18,9 @@ using namespace ipc;
 
 namespace {
 
-constexpr int LoopCount = 10000;
-constexpr int MultiMax  = 8;
+constexpr int LoopCount   = 10000;
+constexpr int MultiMax    = 8;
+constexpr int TestBuffMax = 65536;
 
 struct msg_head {
     int id_;
@@ -28,7 +29,7 @@ struct msg_head {
 class rand_buf : public buffer {
 public:
     rand_buf() {
-        int size = capo::random<>{sizeof(msg_head), 65536}();
+        int size = capo::random<>{sizeof(msg_head), TestBuffMax}();
         *this = buffer(new char[size], size, [](void * p, std::size_t) {
             delete [] static_cast<char *>(p);
         });
@@ -98,6 +99,22 @@ public:
     }
 } const data_set__;
 
+#define IPC_ASSERT_TRUE(condition) \
+    do { \
+        bool check = !!(condition); \
+        GTEST_TEST_BOOLEAN_(check, #condition, false, true, \
+                            GTEST_NONFATAL_FAILURE_); \
+        if (!check) return; \
+    } while (0)
+
+#define IPC_ASSERT_FALSE(condition) \
+    do { \
+        bool check = !!(condition); \
+        GTEST_TEST_BOOLEAN_(!check, #condition, true, false, \
+                            GTEST_NONFATAL_FAILURE_); \
+        if (check) return; \
+    } while (0)
+
 template <relat Rp, relat Rc, trans Ts, typename Que = chan<Rp, Rc, Ts>>
 void test_sr(char const * name, int s_cnt, int r_cnt) {
     ipc_ut::sender().start(static_cast<std::size_t>(s_cnt));
@@ -109,10 +126,10 @@ void test_sr(char const * name, int s_cnt, int r_cnt) {
     for (int k = 0; k < s_cnt; ++k) {
         ipc_ut::sender() << [name, &sw, r_cnt, k] {
             Que que { name, ipc::sender };
-            ASSERT_TRUE(que.wait_for_recv(r_cnt));
+            IPC_ASSERT_TRUE(que.wait_for_recv(r_cnt));
             sw.start();
             for (int i = 0; i < (int)data_set__.get().size(); ++i) {
-                ASSERT_TRUE(que.send(data_set__.get()[i]));
+                IPC_ASSERT_TRUE(que.send(data_set__.get()[i]));
             }
         };
     }
@@ -122,17 +139,17 @@ void test_sr(char const * name, int s_cnt, int r_cnt) {
             Que que { name, ipc::receiver };
             for (;;) {
                 rand_buf got { que.recv() };
-                ASSERT_FALSE(got.empty());
+                IPC_ASSERT_FALSE(got.empty());
                 int i = got.get_id();
                 if (i == -1) {
                     return;
                 }
-                ASSERT_TRUE((i >= 0) && (i < (int)data_set__.get().size()));
+                IPC_ASSERT_TRUE((i >= 0) && (i < (int)data_set__.get().size()));
                 auto const &data_set = data_set__.get()[i];
                 if (data_set != got) {
                     printf("data_set__.get()[%d] != got, size = %zd/%zd\n", 
                             i, data_set.size(), got.size());
-                    ASSERT_TRUE(false);
+                    IPC_ASSERT_TRUE(false);
                 }
             }
         };
@@ -140,7 +157,7 @@ void test_sr(char const * name, int s_cnt, int r_cnt) {
 
     ipc_ut::sender().wait_for_done();
     Que que { name };
-    ASSERT_TRUE(que.wait_for_recv(r_cnt));
+    IPC_ASSERT_TRUE(que.wait_for_recv(r_cnt));
     for (int k = 0; k < r_cnt; ++k) {
         que.send(rand_buf{msg_head{-1}});
     }