IEFBR14 (was Re: IND$FILE)

Eric Smith spacewar at
Mon Nov 19 18:27:34 CST 2018

On Mon, Nov 19, 2018 at 2:24 PM Sean Conner via cctalk <
cctalk at> wrote:

> I've always been amused by IEFBR14 ever since I heard about it.  I first
> came across it by this quote:
>         Every program has at least one bug and can be shortened by at least
>         one instruction---from which, by induction, one can deduce that
>         every program can be reduced to one instruction which doesn't work.
> IEFBR14 was this program---one instruction long, and it contained a bug:

By induction you should be able to reduce a program to zero instructions.
On CP/M, you actually can, and the resulting program is useful, and as far
as I know, has zarro boogs. (Which instruction could a bug be in?)

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