diff --git a/rcl/src/rcl/wait.c b/rcl/src/rcl/wait.c
index 58cc982..76c81e5 100644
--- a/rcl/src/rcl/wait.c
+++ b/rcl/src/rcl/wait.c
@@ -293,6 +293,7 @@ rcl_wait_set_get_allocator(const rcl_wait_set_t * wait_set, rcl_allocator_t * al
     return RCL_RET_OK; \
   } \
   rcl_allocator_t allocator = wait_set->impl->allocator; \
+  wait_set->size_of_ ## Type ## s = 0; \
   if (size == 0) { \
     if (wait_set->Type ## s) { \
       allocator.deallocate((void *)wait_set->Type ## s, allocator.state); \
@@ -300,7 +301,6 @@ rcl_wait_set_get_allocator(const rcl_wait_set_t * wait_set, rcl_allocator_t * al
     } \
     ExtraDealloc \
   } else { \
-    wait_set->size_of_ ## Type ## s = 0; \
     wait_set->Type ## s = (const rcl_ ## Type ## _t * *)allocator.reallocate( \
       (void *)wait_set->Type ## s, sizeof(rcl_ ## Type ## _t *) * size, allocator.state); \
     RCL_CHECK_FOR_NULL_WITH_MSG( \
diff --git a/rcl/test/rcl/test_wait.cpp b/rcl/test/rcl/test_wait.cpp
index 28e96db..ba05214 100644
--- a/rcl/test/rcl/test_wait.cpp
+++ b/rcl/test/rcl/test_wait.cpp
@@ -41,3 +41,18 @@ TEST(CLASSNAME(WaitSetTestFixture, RMW_IMPLEMENTATION), test_resize_to_zero) {
   ret = rcl_wait_set_fini(&wait_set);
   ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
 }
+
+TEST(CLASSNAME(WaitSetTestFixture, RMW_IMPLEMENTATION), test_clear) {
+  // Initialize a waitset with a subscription and then resize it to zero.
+  rcl_wait_set_t wait_set = rcl_get_zero_initialized_wait_set();
+  rcl_ret_t ret = rcl_wait_set_init(&wait_set, 1, 0, 0, 0, 0, rcl_get_default_allocator());
+  ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
+
+  ret = rcl_wait_set_clear_subscriptions(&wait_set);
+  ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
+
+  EXPECT_EQ(wait_set.size_of_subscriptions, 0);
+
+  ret = rcl_wait_set_fini(&wait_set);
+  ASSERT_EQ(RCL_RET_OK, ret) << rcl_get_error_string_safe();
+}