Check that the thread incrementing or decrementing

	the ref count of a Tcl_Obj is the thread that
	originally allocated the thread. This fail fast
	behavior will catch programming errors that
	allow a single Tcl_Obj to be accessed from multiple
	threads.

	* generic/tcl.h (Tcl_Obj): Add allocThread member
	to Tcl_Obj. This member records the thread id the
	Tcl_Obj was allocated. It is used to check that
	any future ref count incr or decr is done from
	the same thread that allocated the Tcl_Obj.
	This member is defined only when threads and
	mem debug are enabled.
	* generic/tclInt.h (TclNewObj, TclDbNewObj,
	TclDecrRefCount):
	Define TclNewObj and TclDbNewObj using TclDbInitNewObj
	when mem debug is enabled. This fixes a problem where
	TclNewObj calls did not work the same as TclDbNewObj
	when mem debug was enabled.
	* generic/tclObj.c (TclDbInitNewObj, Tcl_DbIncrRefCount,
	Tcl_DbDecrRefCount): Add new helper to init Tcl_Obj
	members when mem debug is enabled. Init the allocThread
	member in TclDbInitNewObj and check it in
	Tcl_DbIncrRefCount and Tcl_DbDecrRefCount to make sure
	a Tcl_Obj allocated in one thread is not being acted
	upon in another thread.

1 files changed, 10 insertions, 1 deletions

diff --git a/generic/tcl.h b/generic/tcl.h
index 48a6c15..bbe13a7 100644
--- a/generic/tcl.h
+++ b/generic/tcl.h
@@ -13,7 +13,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tcl.h,v 1.160 2003/07/18 02:02:02 das Exp $
+ * RCS: @(#) $Id: tcl.h,v 1.161 2003/07/22 00:59:58 mdejong Exp $
  */
 
 #ifndef _TCL
@@ -778,6 +778,15 @@ typedef struct Tcl_Obj {
 	    VOID *ptr2;
 	} twoPtrValue;
     } internalRep;
+
+    /*
+     * Thread id used to check that calls to Tcl_IncrRefCount,
+     * Tcl_DecrRefCount, and Tcl_IsShared are being made
+     * from the thread that originally allocated the Tcl_Obj.
+     */
+#if defined(TCL_MEM_DEBUG) && defined(TCL_THREADS)
+    Tcl_ThreadId allocThread;
+#endif
 } Tcl_Obj;