X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;ds=sidebyside;f=lily%2Fgrob-property.cc;h=c4dce927b43f86f3265348779ede3ef846f6b1b9;hb=58a112d5df3f1a8313ee721cea5cd9ce479e2f48;hp=8c68171fa92eaae76f688c8286c475f0384eb4f4;hpb=93f049e9a8e11ed1eabd82103636a227d8902cb8;p=lilypond.git

diff --git a/lily/grob-property.cc b/lily/grob-property.cc
index 8c68171fa9..c4dce927b4 100644
--- a/lily/grob-property.cc
+++ b/lily/grob-property.cc
@@ -55,6 +55,7 @@ Grob::internal_set_property (SCM sym, SCM v)
     {
       if (!ly_is_procedure (v)
 	  && !is_simple_closure (v)
+	  && v != ly_symbol2scm ("calculation-in-progress") 
 	  && !type_check_assignment (sym, v, ly_symbol2scm ("backend-type?")))
 	abort ();
       check_interfaces_for_property (this, sym);