[sgen] Document a shutdown sequence bug.

diff --git a/mono/metadata/monitor.c b/mono/metadata/monitor.c
index 0c457acace4b420feaceac597cdd94b3ce684981..36a42db0bf7d13c23d3969b39cc8195831eb52d3 100644 (file)
--- a/mono/metadata/monitor.c
+++ b/mono/metadata/monitor.c
@@ -153,7 +153,19 @@ mono_monitor_cleanup (void)
        for (mon = monitor_freelist; mon; mon = mon->data)
                mon->wait_list = (gpointer)-1;
 
-       /* FIXME: This still crashes with sgen (async_read.exe) */
+       /*
+        * FIXME: This still crashes with sgen (async_read.exe)
+        *
+        * In mini_cleanup() we first call mono_runtime_cleanup(), which calls
+        * mono_monitor_cleanup(), which is supposed to free all monitor memory.
+        *
+        * Later in mini_cleanup(), we call mono_domain_free(), which calls
+        * mono_gc_clear_domain(), which frees all weak links associated with objects.
+        * Those weak links reside in the monitor structures, which we've freed earlier.
+        *
+        * Unless we fix this dependency in the shutdown sequence this code has to remain
+        * disabled, or at least the call to g_free().
+        */
        /*
        for (marray = monitor_allocated; marray; marray = next) {
                int i;