unnamed bit fields

[utzoo!decvax!ucbvax!unix-wizards]

>From MBM at MIT-XX Thu Nov 12 22:16:30 1981
These dont seem to me to work (Bell v7 compiler).
My impression is that I should be able to say

	struct  { int x : 2; :2; :0; int y; }

where the :2 with no identifer pads 2 unused bits and
the :0 pads to the next word. However, the compiler is
not pleased.  It accepts named bit fields fine though.
I cant find an example of their use; can someone 
enlighten me?
--mike
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