--- a/Makefile.in
+++ b/Makefile.in
@@ -170,17 +170,17 @@ install-manifests: faster
 faster: install-dist/idl
 	$(MAKE) -C faster FASTER_RECURSIVE_MAKE=1
 endif
 
 .PHONY: tup
 tup:
 	$(call BUILDSTATUS,TIERS make tup)
 	$(call BUILDSTATUS,TIER_START make)
-	$(MAKE) install-manifests buildid.h source-repo.h
+	$(MAKE) buildid.h source-repo.h
 	$(call BUILDSTATUS,TIER_FINISH make)
 	$(call BUILDSTATUS,TIER_START tup)
 	@$(TUP) $(if $(findstring s,$(filter-out --%,$(MAKEFLAGS))),,--verbose)
 	$(call BUILDSTATUS,TIER_FINISH tup)
 
 # process_install_manifest needs to be invoked with --no-remove when building
 # js as standalone because automated builds are building nspr separately and
 # that would remove the resulting files.

--- a/python/mozbuild/mozbuild/backend/tup.py
+++ b/python/mozbuild/mozbuild/backend/tup.py
@@ -75,16 +75,29 @@ class BackendTupfile(object):
         self.write(': %(inputs)s |> %(display)s%(cmd)s |> %(outputs)s%(extra_outputs)s\n' % {
             'inputs': ' '.join(inputs),
             'display': '^%s^ ' % caret_text if caret_text else '',
             'cmd': ' '.join(cmd),
             'outputs': ' '.join(outputs),
             'extra_outputs': ' | ' + ' '.join(extra_outputs) if extra_outputs else '',
         })
 
+    def symlink_rule(self, source, output_group=None):
+        outputs = [mozpath.basename(source)]
+        if output_group:
+            outputs.append(output_group)
+
+        # The !tup_ln macro does a symlink or file copy (depending on the
+        # platform) without shelling out to a subprocess.
+        self.rule(
+            cmd=['!tup_ln'],
+            inputs=[source],
+            outputs=outputs,
+        )
+
     def export_shell(self):
         if not self.shell_exported:
             # These are used by mach/mixin/process.py to determine the current
             # shell.
             for var in ('SHELL', 'MOZILLABUILD', 'COMSPEC'):
                 self.write('export %s\n' % var)
             self.shell_exported = True
 
@@ -101,16 +114,20 @@ class TupOnly(CommonBackend, PartialBack
     """
 
     def _init(self):
         CommonBackend._init(self)
 
         self._backend_files = {}
         self._cmd = MozbuildObject.from_environment()
 
+        # This is a 'group' dependency - All rules that list this as an output
+        # will be built before any rules that list this as an input.
+        self._installed_files = '$(MOZ_OBJ_ROOT)/<installed-files>'
+
     def _get_backend_file(self, relativedir):
         objdir = mozpath.join(self.environment.topobjdir, relativedir)
         srcdir = mozpath.join(self.environment.topsrcdir, relativedir)
         if objdir not in self._backend_files:
             self._backend_files[objdir] = \
                     BackendTupfile(srcdir, objdir, self.environment,
                                    self.environment.topsrcdir, self.environment.topobjdir)
         return self._backend_files[objdir]
@@ -128,21 +145,18 @@ class TupOnly(CommonBackend, PartialBack
 
     def consume_object(self, obj):
         """Write out build files necessary to build with tup."""
 
         if not isinstance(obj, ContextDerived):
             return False
 
         consumed = CommonBackend.consume_object(self, obj)
-
-        # Even if CommonBackend acknowledged the object, we still need to let
-        # the RecursiveMake backend also handle these objects.
         if consumed:
-            return False
+            return True
 
         backend_file = self._get_backend_file_for(obj)
 
         if isinstance(obj, GeneratedFile):
             # These files are already generated by make before tup runs.
             skip_files = (
                 'buildid.h',
                 'source-repo.h',
@@ -245,16 +259,20 @@ class TupOnly(CommonBackend, PartialBack
 
     def _process_final_target_pp_files(self, obj, backend_file):
         for i, (path, files) in enumerate(obj.files.walk()):
             for f in files:
                 self._preprocess(backend_file, f.full_path,
                                  destdir=mozpath.join(self.environment.topobjdir, obj.install_target, path))
 
     def _handle_idl_manager(self, manager):
+        dist_idl_backend_file = self._get_backend_file('dist/idl')
+        for idl in manager.idls.values():
+            dist_idl_backend_file.symlink_rule(idl['source'], output_group=self._installed_files)
+
         backend_file = self._get_backend_file('xpcom/xpidl')
         backend_file.export_shell()
 
         for module, data in sorted(manager.modules.iteritems()):
             dest, idls = data
             cmd = [
                 '$(PYTHON_PATH)',
                 '$(PLY_INCLUDE)',
@@ -270,16 +288,17 @@ class TupOnly(CommonBackend, PartialBack
             cmd.extend(sorted(idls))
 
             outputs = ['$(MOZ_OBJ_ROOT)/%s/components/%s.xpt' % (dest, module)]
             outputs.extend(['$(MOZ_OBJ_ROOT)/dist/include/%s.h' % f for f in sorted(idls)])
             backend_file.rule(
                 inputs=[
                     '$(MOZ_OBJ_ROOT)/xpcom/idl-parser/xpidl/xpidllex.py',
                     '$(MOZ_OBJ_ROOT)/xpcom/idl-parser/xpidl/xpidlyacc.py',
+                    self._installed_files,
                 ],
                 display='XPIDL %s' % module,
                 cmd=cmd,
                 outputs=outputs,
             )
 
     def _preprocess(self, backend_file, input_file, destdir=None):
         cmd = self._py_action('preprocessor')