diff --git a/ChangeLog b/ChangeLog
index 3e81850b6..48aec2b71 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,7 @@
 	* Source/NSDistributedNotificationCenter.m: Partially reverted last
 	change ... seemed to cause problems on some systems.
 	* Tools/gdnc.m: ditto.
+	* Source/NSDebug.m: Small thread safely fix.
 
 2003-07-23  Richard Frith-Macdonald <rfm@gnu.org>
 
diff --git a/Source/NSDebug.m b/Source/NSDebug.m
index 40d75417b..28d8c3957 100644
--- a/Source/NSDebug.m
+++ b/Source/NSDebug.m
@@ -28,6 +28,7 @@
 
 #include "config.h"
 #include <stdio.h>
+#include "Foundation/NSData.h"
 #include "Foundation/NSDebug.h"
 #include "Foundation/NSString.h"
 #include "Foundation/NSLock.h"
@@ -423,7 +424,9 @@ GSDebugAllocationClassList()
 const char*
 GSDebugAllocationList(BOOL changeFlag)
 {
-  const char *ans;
+  const char	*ans;
+  NSData	*d;
+
   if (debug_allocation == NO)
     {
       return "Debug allocation system is not active!\n";
@@ -431,9 +434,10 @@ GSDebugAllocationList(BOOL changeFlag)
   if (uniqueLock != nil)
     [uniqueLock lock];
   ans = _GSDebugAllocationList(changeFlag);
+  d = [NSData dataWithBytes: ans length: strlen(ans) + 1];
   if (uniqueLock != nil)
     [uniqueLock unlock];
-  return ans;
+  return (const char*)[d bytes];
 }
 
 static const char*
@@ -520,7 +524,9 @@ _GSDebugAllocationList(BOOL difference)
 const char*
 GSDebugAllocationListAll()
 {
-  const char *ans;
+  const char	*ans;
+  NSData	*d;
+
   if (debug_allocation == NO)
     {
       return "Debug allocation system is not active!\n";
@@ -528,9 +534,10 @@ GSDebugAllocationListAll()
   if (uniqueLock != nil)
     [uniqueLock lock];
   ans = _GSDebugAllocationListAll();
+  d = [NSData dataWithBytes: ans length: strlen(ans)+1];
   if (uniqueLock != nil)
     [uniqueLock unlock];
-  return ans;
+  return (const char*)[d bytes];
 }
 
 static const char*