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From: guy@auspex.auspex.com (Guy Harris)
Newsgroups: comp.unix.questions,comp.unix.internals,comp.unix.programmer,comp.lang.c
Subject: Re: Unix Stack Frame Questions
Message-ID: <7044@auspex.auspex.com>
Date: 5 Apr 91 19:19:29 GMT
References: <125@epic.epic.com> <GOEHRING.91Mar25113709@gnu.ai.mit.edu> <3465@unisoft.UUCP>
Followup-To: comp.unix.questions
Distribution: na
Organization: Auspex Systems, Santa Clara
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>If, of course, you have the registers (68K only have so many).
>If there's not a stack frame, how are parameters passed to the
>function...?

In registers.

>And how would you return...?

The return value might also be in a register.

Of course, at least some systems that pass parameters in registers also
tend to have stack frames (the SPARC calling conventions have them);
however, as indicated, there's no absolute guarantee that automatics are
on the stack frame, as compilers may just stick them in registers (yes,
even if they're not declared "register"), and a compiler might well not
bother allocating a stack frame at all for, say, a leaf procedure, if
there aren't any automatic variables in it.