X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Finclude%2Fsmobs.tcc;h=c0a62535f5e4f830200c8b4a249ae955032d414f;hb=47db9a3883d726ca53e2133a3b2298f78dd6a32e;hp=f927d481d422fda55fd75bdaf502786eb5675d7d;hpb=10d0d9e67d52b1655435cf8e154c13523b9cbef9;p=lilypond.git

diff --git a/lily/include/smobs.tcc b/lily/include/smobs.tcc
index f927d481d4..c0a62535f5 100644
--- a/lily/include/smobs.tcc
+++ b/lily/include/smobs.tcc
@@ -1,7 +1,7 @@
 /* -*- C++ -*-
   This file is part of LilyPond, the GNU music typesetter.
 
-  Copyright (C) 2005--2014 Han-Wen Nienhuys <hanwen@xs4all.nl>
+  Copyright (C) 2005--2015 Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -35,6 +35,13 @@ Smob_base<Super>::mark_trampoline (SCM arg)
   return (Super::unsmob (arg))->mark_smob ();
 }
 
+template <class Super>
+int
+Smob_base<Super>::print_trampoline (SCM arg, SCM port, scm_print_state *p)
+{
+  return (Super::unsmob (arg))->print_smob (port, p);
+}
+
 template <class Super>
 SCM
 Smob_base<Super>::register_ptr (Super *p)
@@ -75,7 +82,7 @@ Smob_base<Super>::equal_p (SCM, SCM)
 
 template <class Super>
 int
-Smob_base<Super>::print_smob (SCM, SCM p, scm_print_state *)
+Smob_base<Super>::print_smob (SCM p, scm_print_state *)
 {
   scm_puts ("#<", p);
   scm_puts (smob_name_.c_str (), p);
@@ -121,9 +128,15 @@ void Smob_base<Super>::init ()
 
   if (&Super::free_smob != &Smob_base<Super>::free_smob)
     scm_set_smob_free (smob_tag_, Super::free_smob);
-  if (&Super::mark_smob != &Smob_base<Super>::mark_smob)
+  // Old GCC versions get their type lattice for pointers-to-members
+  // tangled up to a degree where we need to typecast _both_ covariant
+  // types in order to be able to compare them.  The other comparisons
+  // are for static member functions and thus are ordinary function
+  // pointers which work without those contortions.
+  if (static_cast<SCM (Super::*)()>(&Super::mark_smob) !=
+      static_cast<SCM (Super::*)()>(&Smob_base<Super>::mark_smob))
     scm_set_smob_mark (smob_tag_, Super::mark_trampoline);
-  scm_set_smob_print (smob_tag_, Super::print_smob);
+  scm_set_smob_print (smob_tag_, Super::print_trampoline);
   if (&Super::equal_p != &Smob_base<Super>::equal_p)
     scm_set_smob_equalp (smob_tag_, Super::equal_p);
   if (Super::type_p_name_ != 0)