[Mono-bugs] [Bug 31333][Nor] New - GC problem with Console.WriteLine in the finalization code.

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Changed by manyoso@yahoo.com.

http://bugzilla.ximian.com/show_bug.cgi?id=31333

--- shadow/31333	Thu Sep 26 23:57:22 2002
+++ shadow/31333.tmp.23266	Thu Sep 26 23:57:22 2002
@@ -0,0 +1,101 @@
+Bug#: 31333
+Product: Mono/Runtime
+Version: unspecified
+OS: 
+OS Details: 
+Status: NEW   
+Resolution: 
+Severity: 
+Priority: Normal
+Component: misc
+AssignedTo: mono-bugs@ximian.com                            
+ReportedBy: manyoso@yahoo.com               
+QAContact: mono-bugs@ximian.com
+TargetMilestone: ---
+URL: 
+Cc: 
+Summary: GC problem with Console.WriteLine in the finalization code.
+
+The following code is a test case for something that's been haunting us for quite awhile.  
+For some reason the inclusion of the call to Console.WriteLine is producing hard segv's 
+with curious backtraces in gdb...  The stack frame is _huge_ and it always ends with 
+some finalizer and then some type of threading code.  This also seems dependant upon 
+which version of boehm we use, but the results are always similar.  Here is the code: 
+ 
+using System; 
+using System.Collections; 
+ 
+public class MyClass  
+{ 
+        public int instanceNumber; 
+        private static int classCounter = 0; 
+ 
+        public MyClass() 
+        { 
+                instanceNumber = classCounter++; 
+        }  
+ 
+        ~MyClass() 
+        { 
+               Console.WriteLine("MyClass instance {0} destroyed", instanceNumber); 
+        } 
+} 
+ 
+public class Testing 
+{ 
+        static void Main() 
+        { 
+				ArrayList list = new ArrayList (); 
+                while(true) 
+                { 
+                        MyClass instance = new MyClass(); 
+                        list.Add (new WeakReference(instance)); 
+                } 
+        } 
+} 
+ 
+This produces this kind of output followed by a segv: 
+... 
+MyClass instance 6494 destroyed 
+MyClass instance 6495 destroyed 
+MyClass instance 6496 destroyed 
+MyClass instance 6497 destroyed 
+MyClass instance 6498 destroyed 
+Segmentation fault 
+ 
+The backtrace looks something like this: 
+ 
+Program received signal SIGSEGV, Segmentation fault. 
+[Switching to Thread 1024 (LWP 28859)] 
+0x400f3f68 in __pthread_lock () from /lib/libpthread.so.0 
+(gdb) bt 
+#0  0x400f3f68 in __pthread_lock () from /lib/libpthread.so.0 
+#1  0x400f0e1a in pthread_mutex_lock () from /lib/libpthread.so.0 
+#2  0x0814a63e in EnterCriticalSection (section=0x817d6fc) at critical-sections.c:138 
+#3  0x080d6158 in mono_ldftn (method=0x8242160) at codegen-x86.c:10677 
+#4  0x08246f3d in ?? () 
+#5  0x080e6b6d in mono_jit_runtime_invoke (method=0x8242160, obj=0x8826910, 
+params=0x0, exc=0xbfe011a8) at jit.c:307 
+#6  0x08108e08 in mono_runtime_invoke (method=0x8242160, obj=0x8826910, 
+params=0x0, exc=0xbfe011a8) at object.c:365 
+#7  0x081177a2 in run_finalize (obj=0x8826910, data=0x0) at gc.c:50 
+#8  0x400b5f7c in GC_invoke_finalizers () at finalize.c:789 
+#9  0x400b5fde in GC_notify_or_invoke_finalizers () at finalize.c:816 
+#10 0x400b7031 in GC_generic_malloc (lb=12, k=1) at malloc.c:186 
+#11 0x400b7218 in GC_malloc (lb=12) at malloc.c:309 
+#12 0x08109b8b in mono_object_allocate (size=12) at object.c:732 
+#13 0x08109c3c in mono_object_new_specific (vtable=<incomplete type>) at 
+object.c:786 
+#14 0x08109c09 in mono_object_new (domain=0x81aff60, klass=0x81d45f0) at 
+object.c:771 
+#15 0x080d2ff8 in mono_object_new_wrapper (klass=0x81d45f0) at 
+codegen-x86.c:10420 
+#16 0x0875e227 in ?? () 
+#17 0x08246f4b in ?? () 
+#18 0x080e6b6d in mono_jit_runtime_invoke (method=0x8242160, obj=0x8826930, 
+params=0x0, exc=0xbfe0146c) at jit.c:307 
+#19 0x08108e08 in mono_runtime_invoke (method=0x8242160, obj=0x8826930, 
+params=0x0, exc=0xbfe0146c) at object.c:365 
+---Type <return> to continue, or q <return> to quit--- 
+ 
+The mono_jit_runtime_invoke method is Finalize and the obj is a MyClass...