--- a/build/macosx/universal/flight.mk
+++ b/build/macosx/universal/flight.mk
@@ -18,20 +18,24 @@ endif
 topsrcdir = $(TOPSRCDIR)
 include $(OBJDIR)/config/autoconf.mk
 
 core_abspath = $(if $(filter /%,$(1)),$(1),$(CURDIR)/$(1))
 
 DIST = $(OBJDIR)/dist
 
 postflight_all:
-ifdef ENABLE_TESTS
 	mkdir -p $(DIST_UNI)/$(MOZ_PKG_APPNAME)
 	rm -f $(DIST_ARCH_2)/universal
 	ln -s $(call core_abspath,$(DIST_UNI)) $(DIST_ARCH_2)/universal
+# Stage a package for buildsymbols to be happy. Doing so in OBJDIR_ARCH_1
+# actually does a universal staging with both OBJDIR_ARCH_1 and OBJDIR_ARCH_2.
+	$(MAKE) -C $(OBJDIR_ARCH_1)/$(INSTALLER_DIR) \
+	   PKG_SKIP_STRIP=1 stage-package
+ifdef ENABLE_TESTS
 # Now, repeat the process for the test package.
 	$(MAKE) -C $(OBJDIR_ARCH_1) UNIVERSAL_BINARY= CHROME_JAR= package-tests
 	$(MAKE) -C $(OBJDIR_ARCH_2) UNIVERSAL_BINARY= CHROME_JAR= package-tests
 	rm -rf $(DIST_UNI)/test-package-stage
 # automation.py differs because it hardcodes a path to
 # dist/bin. It doesn't matter which one we use.
 	if test -d $(DIST_ARCH_1)/test-package-stage -a                 \
                 -d $(DIST_ARCH_2)/test-package-stage; then              \

--- a/python/mozbuild/mozpack/files.py
+++ b/python/mozbuild/mozpack/files.py
@@ -134,18 +134,17 @@ class File(BaseFile):
 
 class ExecutableFile(File):
     '''
     File class for executable and library files on OS/2, OS/X and ELF systems.
     (see mozpack.executables.is_executable documentation).
     '''
     def copy(self, dest):
         assert isinstance(dest, basestring)
-        if not File.copy(self, dest):
-            return False
+        File.copy(self, dest)
         try:
             if may_strip(dest):
                 strip(dest)
             if may_elfhack(dest):
                 elfhack(dest)
         except ErrorMessage:
             os.remove(dest)
             raise

--- a/python/mozbuild/mozpack/unify.py
+++ b/python/mozbuild/mozpack/unify.py
@@ -5,16 +5,17 @@
 from mozpack.files import (
     FileFinder,
     ExecutableFile,
     BaseFile,
     GeneratedFile,
 )
 from mozpack.executables import (
     MACHO_SIGNATURES,
+    may_strip,
     strip,
 )
 from mozpack.errors import errors
 from tempfile import mkstemp
 import mozpack.path
 import shutil
 import struct
 import os
@@ -53,17 +54,18 @@ class UnifiedExecutableFile(BaseFile):
         assert isinstance(dest, basestring)
         tmpfiles = []
         try:
             for p in [self.path1, self.path2]:
                 fd, f = mkstemp()
                 os.close(fd)
                 tmpfiles.append(f)
                 shutil.copy2(p, f)
-                strip(f)
+                if may_strip(f):
+                    strip(f)
             subprocess.call(['lipo', '-create'] + tmpfiles + ['-output', dest])
         finally:
             for f in tmpfiles:
                 os.unlink(f)
 
 
 class UnifiedFinder(FileFinder):
     '''

--- a/toolkit/mozapps/installer/l10n-repack.py
+++ b/toolkit/mozapps/installer/l10n-repack.py
@@ -27,16 +27,17 @@ from mozpack.chrome.manifest import (
     is_manifest,
     ManifestChrome,
     Manifest,
 )
 from mozpack.errors import errors
 from mozpack.packager.unpack import UnpackFinder
 from createprecomplete import generate_precomplete
 from argparse import ArgumentParser
+import buildconfig
 
 # Set of files or directories not listed in a chrome.manifest but that are
 # localized.
 NON_CHROME = set([
     '**/crashreporter*.ini',
     'searchplugins',
     'dictionaries',
     'hyphenation',
@@ -181,12 +182,14 @@ def main():
                         help='Directory containing the build to repack')
     parser.add_argument('l10n',
                         help='Directory containing the staged langpack')
     parser.add_argument('--non-resource', nargs='+', metavar='PATTERN',
                         default=[],
                         help='Extra files not to be considered as resources')
     args = parser.parse_args()
 
+    buildconfig.substs['USE_ELF_HACK'] = False
+    buildconfig.substs['PKG_SKIP_STRIP'] = True
     repack(args.build, args.l10n, args.non_resource)
 
 if __name__ == "__main__":
     main()

--- a/toolkit/mozapps/installer/unpack.py
+++ b/toolkit/mozapps/installer/unpack.py
@@ -1,18 +1,21 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import sys
 import os
 from mozpack.packager.unpack import unpack
+import buildconfig
 
 def main():
     if len(sys.argv) != 2:
         print >>sys.stderr, "Usage: %s directory" % \
                             os.path.basename(sys.argv[0])
         sys.exit(1)
 
+    buildconfig.substs['USE_ELF_HACK'] = False
+    buildconfig.substs['PKG_SKIP_STRIP'] = True
     unpack(sys.argv[1])
 
 if __name__ == "__main__":
     main()