--- a/ipc/ipdl/ipdl/lower.py
+++ b/ipc/ipdl/ipdl/lower.py
@@ -3,17 +3,17 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import os, re, sys
 from copy import deepcopy
 
 import ipdl.ast
 import ipdl.builtin
 from ipdl.cxx.ast import *
-from ipdl.type import Actor, ActorType, ProcessGraph, TypeVisitor
+from ipdl.type import Actor, ActorType, ProcessGraph, TypeVisitor, builtinHeaderIncludes
 
 # FIXME/cjones: the chromium Message logging code doesn't work on
 # gcc/POSIX, because it wprintf()s across the chromium/mozilla
 # boundary. one side builds with -fshort-wchar, the other doesn't.
 # this code will remain off until the chromium base lib is replaced
 EMIT_LOGGING_CODE = ('win32' == sys.platform)
 
 ##-----------------------------------------------------------------------------
@@ -1413,16 +1413,18 @@ class _GenerateProtocolCode(ipdl.ast.Vis
 
     def visitTranslationUnit(self, tu):
         hf = self.hdrfile
 
         hf.addthing(_DISCLAIMER)
         hf.addthings(_includeGuardStart(hf))
         hf.addthing(Whitespace.NL)
 
+        for inc in builtinHeaderIncludes:
+            self.visitCxxInclude(inc)
         ipdl.ast.Visitor.visitTranslationUnit(self, tu)
         if tu.filetype == 'header':
             self.cppIncludeHeaders.append(_ipdlhHeaderName(tu))
 
         hf.addthing(Whitespace.NL)
         hf.addthings(_includeGuardEnd(hf))
 
         cf = self.cppfile

--- a/ipc/ipdl/ipdl/type.py
+++ b/ipc/ipdl/ipdl/type.py
@@ -592,18 +592,16 @@ With this information, it finally type c
     def check(self, tu, errout=sys.stderr):
         def runpass(tcheckpass):
             tu.accept(tcheckpass)
             if len(self.errors):
                 self.reportErrors(errout)
                 return False
             return True
 
-        tu.cxxIncludes = builtinHeaderIncludes + tu.cxxIncludes
-
         # tag each relevant node with "decl" information, giving type, name,
         # and location of declaration
         if not runpass(GatherDecls(builtinUsing, self.errors)):
             return False
 
         # now that the nodes have decls, type checking is much easier.
         if not runpass(CheckTypes(self.errors)):
             return False