One of our Q3 goals is to refactor the |make export| tier to not rely on recursive traversal. This essentially means moving all of the "export" targets into non-recursive make files or alternative mechanisms. We will likely still have an |export| target and tier, but they will be radically different. We should work towards no-op builds during |make export|. Although, I'm not sure if this will be completely achievable due to external build systems and incomplete moz.build port. This is a tracking bug. I'll collect all action items as dependencies.

The following contain an export target: Makefile.in accessible/public/msaa/Makefile.in browser/metro/shell/Makefile.in build/Makefile.in config/Makefile.in config/nspr/Makefile.in db/sqlite3/src/Makefile.in ipc/chromium/Makefile.in ipc/ipdl/Makefile.in media/mtransport/build/Makefile.in media/mtransport/standalone/Makefile.in mobile/android/branding/aurora/content/Makefile.in mobile/android/branding/beta/content/Makefile.in mobile/android/branding/nightly/content/Makefile.in mobile/android/branding/official/content/Makefile.in mobile/android/branding/unofficial/content/Makefile.in mobile/locales/Makefile.in probes/Makefile.in profile/dirserviceprovider/standalone/Makefile.in security/build/Makefile.in security/nss/tests/pkcs11/netscape/trivial/Makefile.in toolkit/Makefile.in toolkit/components/urlformatter/Makefile.in toolkit/library/Makefile.in toolkit/profile/Makefile.in widget/cocoa/Makefile.in widget/os2/Makefile.in widget/qt/faststartupqt/Makefile.in widget/windows/winrt/Makefile.in xpcom/build/Makefile.in xpcom/glue/nomozalloc/Makefile.in xpcom/glue/standalone/Makefile.in xpcom/glue/standalone/staticruntime/Makefile.in xpcom/glue/staticruntime/Makefile.in xpcom/idl-parser/Makefile.in xpcom/typelib/xpidl/Makefile.in xpcom/typelib/xpt/src/Makefile.in xpcom/typelib/xpt/tools/Makefile.in xulrunner/app/Makefile.in xulrunner/installer/windows/Makefile.in Some of these involve defining the target itself, so they are legit. Many of these targets define simple code generation invocations and could go after work in bug 883954 enables them. There are still some "special" variables (like INSTALL_TARGETS) that result in export rules. I'll have to write a custom query to identify these.