Re: possible gdb agent expression extension

Eli Zaretskii <[email protected]> wrote:

> > Date: Mon, 25 Aug 2014 10:03:03 -0400
> > From: David Taylor <[email protected]>
> > 
> > > That @result{} at the end, with nothing after it, does look strange:
> > > what "result" does this give?
> > 
> > I was largely copying snippets I found nearby in the agentexpr.texi
> > file.  They are of the form:
> > 
> > <agent-opcode> <additional items in the agent byte stream> :
> >     <items on the stack at start of operation> ==>
> >     <items on the stack at end of operation>
> 
> Right, but in your case there's nothing after ==>, which is
> unexpected.
> 
> Thanks.

Right.  Like

    if_goto (0x20) offset : a ==>

    goto (0x21) offset : ==>

    trace (0x0c) : addr size ==>

    tracenz (0x2f) : addr size ==>

    printf (0x34) numargs string : ==>

    end (0x27) : ==>

it means that inputs -- if any -- are consumed; nothing is pushed on the
stack.

[Aside: the documentation is missing the ':' on tracenz and printf.  For
that matter, documentation for printf is missing some other stuff, too.]