Comment 5 for bug 687406

Thanks Tang for the explanation!

I can make an upstream bug about this too, I'll paste the link here once I've done it.

Since the bug is about preprocessing then this also has implications to distributed building like using distcc or icecc. I reported this problem originally because it was noticed that building linux kernel locally or with distcc results in these kinds of differences code. I'm told the kernel uses constructs like these somewhere in local_irq_restore().

Then it was also noticed that -save-temps causes the problem.