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From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Subject: Re: [TUHS] Fwd: Choice of Unix for 11/03 and 11/23+ Systems
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    > I suspect there must be an issue with the -11/05 emulation in Ersatz-11

There is. The C compiler on MiniUnix emits SOB instructions. The -11/05 doesn't
implement SOB; however, the instruction emulator in MiniUnix (emul.s) is
prepared to emulate it. (So MiniUnix should work fine on real -11/05's.)

However, when set to an -11/05, Ersatz-11 treats SOBs as NOPs; they fall
through without any effect. Without a trap, they can't be emulated either.

This caused the problem with namei() failing (namei() calls bcopy(), which has
a SOB in it), and probably caused the problem I was seeing with the C
compiler, but I'm too burned out to check right now. Tomorrow.

    Noel