jump.c (jump_optimize_1): Only set CAN_REACH_END if calculate_can_reach_end returns nonzero.

        * jump.c (jump_optimize_1): Only set CAN_REACH_END if
        calculate_can_reach_end returns nonzero.

From-SVN: r27281

gcc/ChangeLog

@@ -18,6 +18,9 @@ Mon May 31 11:40:20 EDT 1999  John Wehle  (john@feith.com)
 
 Mon May 31 00:46:17 1999  Jeffrey A Law  (law@cygnus.com)
 
+	* jump.c (jump_optimize_1): Only set CAN_REACH_END if 
+	calculate_can_reach_end returns nonzero.
+
 	* configure.in (native gas tests): Search for an assembler in the
 	same manner that the installed compiler will.
 	* configure: Rebuilt.

gcc/jump.c

@@ -235,7 +235,12 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan, mark_labels_only)
 
   if (!optimize)
     {
-      can_reach_end = calculate_can_reach_end (last_insn, 1, 0);
+      /* CAN_REACH_END is persistent for each function.  Once set it should
+	 not be cleared.  This is especially true for the case where we
+	 delete the NOTE_FUNCTION_END note.  CAN_REACH_END is cleared by
+	 the front-end before compiling each function.  */
+      if (calculate_can_reach_end (last_insn, 1, 0))
+	can_reach_end = 1;
 
       /* Zero the "deleted" flag of all the "deleted" insns.  */
       for (insn = f; insn; insn = NEXT_INSN (insn))
@@ -2068,7 +2073,12 @@ jump_optimize_1 (f, cross_jump, noop_moves, after_regscan, mark_labels_only)
     }
 #endif
 
-  can_reach_end = calculate_can_reach_end (last_insn, 0, 1);
+  /* CAN_REACH_END is persistent for each function.  Once set it should
+     not be cleared.  This is especially true for the case where we
+     delete the NOTE_FUNCTION_END note.  CAN_REACH_END is cleared by
+     the front-end before compiling each function.  */
+  if (calculate_can_reach_end (last_insn, 0, 1))
+    can_reach_end = 1;
 
   /* Show JUMP_CHAIN no longer valid.  */
   jump_chain = 0;