Re: [PATCH] Remove gratuitous demangler differences

[Daniel Berlin <dberlin at redhat dot com>]

On 11 Feb 2001, Jason Merrill wrote:

> >>>>> "Daniel" == Daniel Berlin <dberlin@redhat.com> writes:
>
> > On 11 Feb 2001, Jason Merrill wrote:
>
> >> >>>>> "Gabriel" == Gabriel Dos Reis <gdr@codesourcery.com> writes:
> >>
> >> > If your change is mandated by the ABI (that wasn't clear from your
> >> > original message) then it is fine
> >>
> >> It isn't.  The ABI makes no attempt to mandate the output of the demangler.
>
> > However, the ABI does, as I pointed out say j is "unsigned int", not
> > "unsigned", and v is "void", not "void unless the parameter list is
> > empty".
>
> Yes.  But IMO that should not be taken to indicate anything about the
> committee's intent.  In fact, Alex Samuel, who wrote the new demangler,
> also wrote most of the ABI mangling document.

Okeydokey.

>
> >> Daniel's changes are intended to make the new demangler output look like
> >> the old demangler output.  This seems reasonable to me, though another way
> >> to handle this would be to fix the GDB tests to match the new demangler.
>
> > I don't believe it's just GDB that expects this.
>
> Is anyone aware of another example?

Personally, I have some perl scripts that broke as well (They expected
(void) for no parameters.).

It also completely broke unit tests for a debugger I wrote for BeOS (never
released).


>
> > But, regardless, this is *not* a simple task. You really have to come up
> > with new regular expressions just to match the output, because it's not
> > just whitespace differences (which would be relatively easy to handle).
>
> > A compromise would be to make it output "unsigned int" for j, and "void"
> > always for v. Then you'd only be left with whitespace differences.
>
> I can certainly imagine that 'unsigned int' would be easier to catch using
> regexps, avoiding confusion with other unsigned types, so this change makes
> sense to me (for C++STYLE as well as the demangler).
>
> 'void' doesn't seem as clear, though.  grepping for '()' seems just as easy
> as grepping for '(void)', and more accurate than grepping for just 'void'.


Okay, ....
>
> > Or, i'll happily make it DMGL_GDB or DMGL_COMPAT or something of the sort.
>
> I'm opposed to this.

And herein lies the problem. People are opposed to at least one of the
solutions.
:)

>
> Jason
>