# HG changeset patch
# User wenzelm
# Date 1361458848 -3600
# Node ID 8333c10d1a6d278f7c9330f6b5a912da523ab27b
# Parent  7b0c723562af1a3f1b198d47af5d246cd9e1ce4a# Parent  76c062c3323ca1d24cdefb1ad3141945caa75513
merged

diff -r 76c062c3323c -r 8333c10d1a6d src/Pure/Isar/toplevel.ML
--- a/src/Pure/Isar/toplevel.ML	Thu Feb 21 15:35:09 2013 +0100
+++ b/src/Pure/Isar/toplevel.ML	Thu Feb 21 16:00:48 2013 +0100
@@ -718,9 +718,10 @@
         val (body_trs, end_tr) = split_last proof_trs;
         val finish = Context.Theory o Proof_Context.theory_of;
 
-        val timing_estimate = fold (curry Time.+ o get_timing) proof_trs Time.zeroTime;
-        val timing_order = Real.floor (Real.max (Math.log10 (Time.toReal timing_estimate), ~3.0));
-        val pri = Int.min (timing_order - 3, ~1);
+        val estimate = fold (curry Time.+ o get_timing) proof_trs Time.zeroTime;
+        val pri =
+          if estimate = Time.zeroTime then ~1
+	  else Int.min (Real.floor (Real.max (Math.log10 (Time.toReal estimate), ~3.0)) - 3, ~1);
 
         val future_proof = Proof.global_future_proof
           (fn prf =>