From: Neil Puttock <n.puttock@gmail.com>
Date: Mon, 20 Sep 2010 22:13:02 +0000 (+0100)
Subject: Fix #818.
X-Git-Tag: release/2.13.34-1~6
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=c115eee78ce32dab7ee8b8e9a3f24836ab7f5211;p=lilypond.git

Fix #818.

Use unsmob_engraver ()/unsmob_performer () instead of
explicit casting in translator-group.cc when filtering
translators added via \with { }

* lily/include/performer.hh, lily/performer.hh

  add unsmob_performer ()

* lily/translator-group.cc (filter_engravers/filter_performers):

  use unsmob_* () instead of dynamic_cast when checking
  translator is of correct class to remove
---

diff --git a/input/regression/filter-translators.ly b/input/regression/filter-translators.ly
new file mode 100644
index 0000000000..1c10a223f5
--- /dev/null
+++ b/input/regression/filter-translators.ly
@@ -0,0 +1,21 @@
+\version "2.13.34"
+
+\header {
+  texidoc = "Context modification via @code{\\with} filters translators
+of the wrong type: performers for an @code{Engraver_group} and engravers
+for a @code{Performer_group}.  In this test, the
+@code{Instrument_name_engraver} is added to a @code{StaffGroup}, but
+does not affect midi output, since it is filtered out."
+}
+
+\score {
+  \new StaffGroup \with {
+    \consists "Instrument_name_engraver"
+    instrumentName = #"StaffGroup"
+  }
+  {
+    a'1
+  }
+  \layout { }
+  \midi { }
+}
diff --git a/lily/include/performer.hh b/lily/include/performer.hh
index 11a5c32c8a..0b0497e322 100644
--- a/lily/include/performer.hh
+++ b/lily/include/performer.hh
@@ -40,5 +40,7 @@ protected:
   virtual void create_audio_elements ();
 };
 
+Performer *unsmob_performer (SCM perf);
+
 #endif /* PERFORMER_HH */
 
diff --git a/lily/performer.cc b/lily/performer.cc
index c177f9e975..60a0519d42 100644
--- a/lily/performer.cc
+++ b/lily/performer.cc
@@ -19,6 +19,7 @@
 */
 
 #include "context.hh"
+#include "performer.hh"
 #include "performer-group.hh"
 #include "warn.hh"
 
@@ -48,3 +49,9 @@ Performer::announce_element (Audio_element_info i)
 
   get_daddy_performer ()->announce_element (i);
 }
+
+Performer *
+unsmob_performer (SCM perf)
+{
+  return dynamic_cast<Performer *> (unsmob_translator (perf));
+}
diff --git a/lily/translator-group.cc b/lily/translator-group.cc
index 84a97bf52e..f9812e9798 100644
--- a/lily/translator-group.cc
+++ b/lily/translator-group.cc
@@ -23,11 +23,13 @@
 #include "context-def.hh"
 #include "context.hh"
 #include "dispatcher.hh"
+#include "engraver.hh"
 #include "engraver-group.hh"
 #include "international.hh"
 #include "main.hh"
 #include "music.hh"
 #include "output-def.hh"
+#include "performer.hh"
 #include "performer-group.hh"
 #include "scheme-engraver.hh"
 #include "scm-hash.hh"
@@ -52,7 +54,7 @@ Translator_group::connect_to_context (Context *c)
   if (context_)
     {
       programming_error ("translator group is already connected to context "
-			 +  context_->context_name ());
+			 + context_->context_name ());
     }
   
   context_ = c;
@@ -84,13 +86,22 @@ Translator_group::finalize ()
 {
 }
 
+/*
+  Both filter_performers and filter_engravers used to use a direct dynamic_cast
+  on the unsmobbed translator to be filtered, i.e.,
+
+  if (dynamic_cast<Performer *> (unsmob_translator (scm_car (*tail))))
+
+  but this caused mysterious optimisation issues in several GUB builds.  See
+  issue #818 for the background to this change.
+*/
 SCM
 filter_performers (SCM ell)
 {
   SCM *tail = &ell;
   for (SCM p = ell; scm_is_pair (p); p = scm_cdr (p))
     {
-      if (dynamic_cast<Performer *> (unsmob_translator (scm_car (*tail))))
+      if (unsmob_performer (scm_car (*tail)))
 	*tail = scm_cdr (*tail);
       else
 	tail = SCM_CDRLOC (*tail);
@@ -104,7 +115,7 @@ filter_engravers (SCM ell)
   SCM *tail = &ell;
   for (SCM p = ell; scm_is_pair (p); p = scm_cdr (p))
     {
-      if (dynamic_cast<Engraver *> (unsmob_translator (scm_car (*tail))))
+      if (unsmob_engraver (scm_car (*tail)))
 	*tail = scm_cdr (*tail);
       else
 	tail = SCM_CDRLOC (*tail);