A thought on this: The C compiler actually produces assembler, which can be (fairly easily) visually audited; yes, yes, I know about disassembly, but trust me, having done some recently (the RL bootstrap(s)), disassembled code is a lot harder to grok! So, really, to find the Thompson hack, we'd have to edit the binaries of the assembler! For real grins, we could write a program to convert .s format assembler to .mac syntax, run the results through Macro-11, and link it with the other linker... :-) Also, I found on what's going on here: the The C compiler is linked with the -n flag, which produces pure code. What the linker documentation doesn't say (and I never realized this 'back in the day') is that when this option is used, it rounds up the size of the text segment to the nearest click (0100). So, in c2 (which is what I was looking at), the last instruction is at 015446, _etext is at 015450, but if you look at the executable header, it lists a text size of 015500 - i.e. 030 more bytes. And indeed there are 014 words of '0' in the executable file before the data starts. And if you link c2 _without_ the -n flag, it shows 015450 in the header as the text size. So that's why the two versions of all the C compiler phases were the same size (as files); it rounded up to the same place in both, hiding the one-word difference in text size. Noel _______________________________________________ TUHS mailing list TUHS(a)minnie.tuhs.org https://minnie.tuhs.org/mailman/listinfo/tuhs