diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ad5ebc50417..a24977720e7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -3,6 +3,8 @@
 	* flow.c (split_edge): Don't allocate global_live_at_start for
 	the new block unless the old blocks had them as well.
 
+	* flow.c (mark_set_1): Respect not_dead when updating reg_live.
+
 2000-05-06  Zack Weinberg  <zack@wolery.cumb.org>
 
  	* cpphash.h: Remove conditional #define of __extension__.
diff --git a/gcc/flow.c b/gcc/flow.c
index fa4e11a2615..2adad8c9162 100644
--- a/gcc/flow.c
+++ b/gcc/flow.c
@@ -4373,6 +4373,7 @@ mark_set_1 (pbi, code, reg, cond, insn, flags)
 
       /* Mark the register as being dead.  */
       if (some_was_live
+	  && ! not_dead
 	  /* The stack pointer is never dead.  Well, not strictly true,
 	     but it's very difficult to tell from here.  Hopefully
 	     combine_stack_adjustments will fix up the most egregious