diff --git a/boehm-gc/ChangeLog b/boehm-gc/ChangeLog
index 2c8ab1a7a05..dc365819d4e 100644
--- a/boehm-gc/ChangeLog
+++ b/boehm-gc/ChangeLog
@@ -1,3 +1,8 @@
+2002-06-28  Hans Boehm <Hans_Boehm@hp.com>
+            Jonathan Clark
+
+        * win32_threads.c (GC_push_all_stacks): Tolerate bad sp.
+
 2002-06-09  H.J. Lu  (hjl@gnu.org)
 
 	* include/private/gc_locks.h (GC_test_and_set): Support
diff --git a/boehm-gc/win32_threads.c b/boehm-gc/win32_threads.c
index 38de099fa87..d5e3920cbe4 100644
--- a/boehm-gc/win32_threads.c
+++ b/boehm-gc/win32_threads.c
@@ -144,8 +144,15 @@ void GC_push_all_stacks()
     	  GC_push_one ((word) thread_table[i].context.Edx);
     	  GC_push_one ((word) thread_table[i].context.Ecx);
     	  GC_push_one ((word) thread_table[i].context.Eax);
-	  GC_push_all_stack((char *) thread_table[i].context.Esp,
-			    thread_table[i].stack);
+	  if (thread_table[i].context.Esp >= (DWORD)thread_table[i].stack
+	      || thread_table[i].context.Esp < (DWORD)bottom) {
+	      WARN("Thread stack pointer 0x%lx out of range, pushing everything",
+		   thread_table[i].context.Esp);
+	      GC_push_all_stack((char *) bottom, thread_table[i].stack);
+	  } else {
+	      GC_push_all_stack((char *) thread_table[i].context.Esp,
+			        thread_table[i].stack);
+	  }
 #       else
 #       ifdef ARM32
 	  if (thread_table[i].context.Sp >= (DWORD)thread_table[i].stack