diff -r 9a50ea544fd3 -r 150aa3015c47 src/HOL/Tools/Sledgehammer/sledgehammer_prover_minimize.ML
--- a/src/HOL/Tools/Sledgehammer/sledgehammer_prover_minimize.ML	Fri Oct 02 21:06:32 2015 +0200
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_prover_minimize.ML	Fri Oct 02 21:06:32 2015 +0200
@@ -88,8 +88,8 @@
 
     val facts = facts |> maps (fn (n, ths) => map (pair n) ths)
     val params =
-      {debug = debug, verbose = verbose, overlord = overlord, spy = spy, blocking = true,
-       provers = provers, type_enc = type_enc, strict = strict, lam_trans = lam_trans,
+      {debug = debug, verbose = verbose, overlord = overlord, spy = spy, provers = provers,
+       type_enc = type_enc, strict = strict, lam_trans = lam_trans,
        uncurried_aliases = uncurried_aliases, learn = false, fact_filter = NONE,
        max_facts = SOME (length facts), fact_thresholds = (1.01, 1.01),
        max_mono_iters = max_mono_iters, max_new_mono_instances = max_new_mono_instances,