--- /dev/null
+From 42cb7d446827dce32a42b5b243bda522518b3d46 Mon Sep 17 00:00:00 2001
+From: Julien Rioux <julien.rioux@gmail.com>
+Date: Mon, 2 Sep 2013 10:41:50 +0200
+Subject: [PATCH] Keep bison-generated files in sync.
+
+Use a single rule to build header and source files from
+the syntax file, thus avoiding any possibility to have
+`make' rebuild one but not the other, which might happen
+if the syntax and target files have almost the same but
+slightly differing timestamps.
+
+See http://www.mail-archive.com/bug-lilypond@gnu.org/msg37081.html
+
+Fixes issue 3528: Keep bison-generated files in sync.
+http://code.google.com/p/lilypond/issues/detail?id=3528
+---
+ stepmake/stepmake/c++-rules.make | 9 ++-------
+ stepmake/stepmake/c-rules.make | 10 ++--------
+ 2 files changed, 4 insertions(+), 15 deletions(-)
+
+diff --git a/stepmake/stepmake/c++-rules.make b/stepmake/stepmake/c++-rules.make
+index a368f4f..8de00bc 100644
+--- a/stepmake/stepmake/c++-rules.make
++++ b/stepmake/stepmake/c++-rules.make
+@@ -12,13 +12,8 @@ $(outdir)/%.lo: %.cc
+ $(outdir)/%.lo: $(outdir)/%.cc
+ $(DO_LO_DEP) $(CXX) -c $(ALL_CXXFLAGS) $(PIC_FLAGS) -o $@ $<
+
+-$(outdir)/%.cc: %.yy
+- $(BISON) -o $@ $<
+-
+-$(outdir)/%.hh: %.yy
+- $(BISON) -o $(subst .hh,-tmp.cc,$@) -d $<
+- rm $(subst .hh,-tmp.cc,$@)
+- mv $(subst .hh,-tmp.hh,$@) $@
++$(outdir)/%.cc $(outdir)/%.hh: %.yy
++ $(BISON) -d -o $(outdir)/$*.cc $<
+
+ $(outdir)/%.cc: %.ll
+ $(FLEX) -Cfe -p -p -o$@ $<
+diff --git a/stepmake/stepmake/c-rules.make b/stepmake/stepmake/c-rules.make
+index 620275b..954e7a3 100644
+--- a/stepmake/stepmake/c-rules.make
++++ b/stepmake/stepmake/c-rules.make
+@@ -12,14 +12,8 @@ $(outdir)/%.lo: %.c
+ $(outdir)/%.lo: %.c
+ $(DO_LO_DEP) $(CC) -c $(ALL_CFLAGS) $(PIC_FLAGS) -o $@ $<
+
+-$(outdir)/%.c: %.y
+- $(BISON) $<
+- mv $(*F).tab.c $@
+-
+-$(outdir)/%.h: %.y
+- $(BISON) -d $<
+- mv $(*F).tab.h $@
+- rm -f $(*F).tab.c # if this happens in the wrong order it triggers recompile of the .cc file
++$(outdir)/%.c $(outdir)/%.h: %.y
++ $(BISON) -d -o $(outdir)/$*.c $<
+
+ $(outdir)/%.c: %.l
+ $(FLEX) -Cfe -p -p -o$@ $<
+--
+1.8.4.rc3