diff -r 0aa205436740 -r 9b9cd17a0791 src/SConscript
--- a/src/SConscript	Tue Dec 21 08:23:53 2010 -0800
+++ b/src/SConscript	Tue Dec 21 08:24:23 2010 -0800
@@ -61,17 +61,22 @@
         super(SourceMeta, cls).__init__(name, bases, dict)
         cls.all = []
         
-    def get(cls, **kwargs):
+    def get(cls, **flags):
         for src in cls.all:
-            for attr,value in kwargs.iteritems():
-                if getattr(src, attr) != value:
+            for flag,value in flags.iteritems():
+                # if the flag is found and has a different value, skip
+                # this file
+                if src.all_flags.get(flag, False) != value:
                     break
             else:
                 yield src
 
 class SourceFile(object):
     __metaclass__ = SourceMeta
-    def __init__(self, source):
+    def __init__(self, source, parent=None, **flags):
+        self.flags = flags
+        self.parent = parent
+
         tnode = source
         if not isinstance(source, SCons.Node.FS.File):
             tnode = File(source)
@@ -92,6 +97,15 @@
             if issubclass(base, SourceFile):
                 base.all.append(self)
 
+    @property
+    def all_flags(self):
+        flags = {}
+        if self.parent:
+            flags.update(self.parent.flags)
+        flags.update(self.flags)
+        return flags
+
+
     def __lt__(self, other): return self.filename < other.filename
     def __le__(self, other): return self.filename <= other.filename
     def __gt__(self, other): return self.filename > other.filename
@@ -101,14 +115,11 @@
         
 class Source(SourceFile):
     '''Add a c/c++ source file to the build'''
-    def __init__(self, source, Werror=True, swig=False, bin_only=False,
-                 skip_lib=False):
-        super(Source, self).__init__(source)
+    def __init__(self, source, Werror=True, swig=False, **flags):
+        super(Source, self).__init__(source, **flags)
 
         self.Werror = Werror
         self.swig = swig
-        self.bin_only = bin_only
-        self.skip_lib = bin_only or skip_lib
 
 class PySource(SourceFile):
     '''Add a python source file to the named package'''
@@ -117,8 +128,8 @@
     tnodes = {}
     symnames = {}
     
-    def __init__(self, package, source):
-        super(PySource, self).__init__(source)
+    def __init__(self, package, source, **flags):
+        super(PySource, self).__init__(source, **flags)
 
         modname,ext = self.extname
         assert ext == 'py'
@@ -168,8 +179,8 @@
 class SwigSource(SourceFile):
     '''Add a swig file to build'''
 
-    def __init__(self, package, source):
-        super(SwigSource, self).__init__(source)
+    def __init__(self, package, source, **flags):
+        super(SwigSource, self).__init__(source, **flags)
 
         modname,ext = self.extname
         assert ext == 'i'
@@ -178,8 +189,8 @@
         cc_file = joinpath(self.dirname, modname + '_wrap.cc')
         py_file = joinpath(self.dirname, modname + '.py')
 
-        self.cc_source = Source(cc_file, swig=True)
-        self.py_source = PySource(package, py_file)
+        self.cc_source = Source(cc_file, swig=True, parent=self)
+        self.py_source = PySource(package, py_file, parent=self)
 
 unit_tests = []
 def UnitTest(target, sources):
@@ -824,8 +835,9 @@
 
         return obj
 
-    static_objs = [ make_obj(s, True) for s in Source.get(skip_lib=False)]
-    shared_objs = [ make_obj(s, False) for s in Source.get(skip_lib=False)]
+    sources = Source.get(main=False, skip_lib=False)
+    static_objs = [ make_obj(s, True) for s in sources ]
+    shared_objs = [ make_obj(s, False) for s in sources ]
 
     static_date = make_obj(date_source, static=True, extra_deps=static_objs)
     static_objs.append(static_date)
@@ -843,12 +855,13 @@
         new_env.Program("unittest/%s.%s" % (target, label), objs + static_objs)
 
     # Now link a stub with main() and the static library.
-    bin_objs = [make_obj(s, True) for s in Source.get(bin_only=True) ]
+    main_objs = [ make_obj(s, True) for s in Source.get(main=True) ]
+
     progname = exename
     if strip:
         progname += '.unstripped'
 
-    targets = new_env.Program(progname, bin_objs + static_objs)
+    targets = new_env.Program(progname, main_objs + static_objs)
 
     if strip:
         if sys.platform == 'sunos5':
diff -r 0aa205436740 -r 9b9cd17a0791 src/sim/SConscript
--- a/src/sim/SConscript	Tue Dec 21 08:23:53 2010 -0800
+++ b/src/sim/SConscript	Tue Dec 21 08:24:23 2010 -0800
@@ -39,7 +39,7 @@
 Source('debug.cc')
 Source('eventq.cc')
 Source('init.cc')
-Source('main.cc', bin_only=True)
+Source('main.cc', main=True, kip_lib=True)
 Source('root.cc')
 Source('serialize.cc')
 Source('sim_events.cc')