Re: %union errors that shouldn't be there

[Hans Aberg]

At 11:55 +0100 2005/03/21, Laurence Finston wrote:
> On Sun, 20 Mar 2005, DYP wrote:
>
> >  In file included from misery.ll:30:
> >  gram.yy:26: error: ISO C++ forbids declaration of `astNode' with no type
> >  gram.yy:26: error: expected `;' before '*' token
> >  gram.yy:27: error: ISO C++ forbids declaration of `string' with no type
> >  gram.yy:27: error: expected `;' before '*' token
> >  gram.yy:28: error: ISO C++ forbids declaration of `nodeList' with no
> >  type
> >  gram.yy:28: error: expected `;' before '*' token
>
> Apparently, your types `astNode', `string', and `nodeList' are undefined
> when your `%union' declaration is being compiled.  Assuming you're using
> C, My guess is that you're not including the header file or files that
> declare them in your parser input file.  On the other hand, if you're
> using C++, it might be because these are types that can't be included in
> `unions'.  I don't remember the rule off-hand --- it has something to do
> with constructors and/or destructors.  I don't know whether this
> programming error would cause this particular compiler error to be
> signalled, though, and I don't have time to test this myself at the
> moment.

They should be OK in C++, as pointers do not have non-trival 
con-/de-structors. The compiler needs to see a declaration of the 
name as a type, though, before it sees the pointer.
--
  Hans Aberg