Re: [Qemu-devel] [PATCH] Separate function types from opaque types in include/qemu/typedefs.h

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Greg Kurz (groug@kaod.org) wrote:
> On Thu, 22 Jun 2017 18:25:55 +0100
> "Dr. David Alan Gilbert" <dgilbert@redhat.com> wrote:
> 
> > * Peter Maydell (peter.maydell@linaro.org) wrote:
> > > On 22 June 2017 at 18:03, Juan Quintela <quintela@redhat.com> wrote:  
> > > > Greg Kurz <groug@kaod.org> wrote:  
> > > >> On Thu, 22 Jun 2017 17:14:08 +0100
> > > >> Peter Maydell <peter.maydell@linaro.org> wrote:
> > > >>  
> > > >>> On 22 June 2017 at 17:06, Greg Kurz <groug@kaod.org> wrote:  
> > > >>> > Function types cannot reside in the same sorted list as opaque types since
> > > >>> > they may depend on a type which would be defined later.
> > > >>> >
> > > >>> > Of course, the same problem could arise if a function type depends on
> > > >>> > another function type with greater alphabetical order. Hopefully we
> > > >>> > don't have that at this time.  
> > > >>>
> > > >>> The other approach would be to put function types somewhere
> > > >>> else and leave typedefs.h for the simple 'opaque types
> > > >>> for structures' that it was started as.
> > > >>>
> > > >>> For instance we have include/qemu/fprintf-fn.h as a precedent.
> > > >>>  
> > > >>
> > > >> Indeed, and I'm not quite sure why Juan decided to put these types into
> > > >> typedefs.h instead of a dedicated header file in include/migration... is
> > > >> it only because it was the quickest fix ?  
> > > >
> > > > All other typedefs were defined there.  I can create a different include
> > > > file, but I think that is "overengineering", no?  They are typedefs,
> > > > just not of structs.  But I agree that they are the only ones.  
> > > 
> > > Well, the comment in the file says "opaque types so that device init
> > > declarations don't have to pull in all the real definitions", whereas
> > > the ones you've added aren't opaque types, they are the real
> > > definitions. They're also only used by a very small subset of .c
> > > files, whereas typedefs.h goes everywhere.  
> > 
> > mv fprintf-fn.f   fn-typedefs.h
> > 
> > move those two defs into that?
> > 
> 
> Wouldn't it be more appropriate to put them in a dedicated
> include/migration/handler-fn.h header included by both
> vmstate.h and register.h ?

Could do; I'm just not finding tiny header files with one or
two entries each that useful.

Dave

> > Dave
> > 
> > > thanks
> > > -- PMM  
> > --
> > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
> > 
> 


--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK