Re: [Qemu-devel] [PATCH v2] Drop --whole-archive and static libraries

[Andreas Färber]

Am 04.01.2010 um 21:47 schrieb Blue Swirl:

> On Sun, Jan 3, 2010 at 12:31 PM, Blue Swirl <address@hidden>  
> wrote:
> > 2009/12/31 Andreas Färber <address@hidden>:
> > > From: Andreas Färber <address@hidden>
> > >
> > > Juan has contributed a cool Makefile infrastructure that enables  
> > > us to drop
> > > static libraries completely:
> > >
> > > Move shared obj-y definitions to Makefile.objs, prefixed  
> > > {common-,hw-,user-},
> > > and link those object files directly into the executables.
> > >
> > > Replace HWLIB by HWDIR, specifying only the directory.
> > >
> > > Drop --whole-archive and ARLIBS in Makefiles and configure.
> > >
> > > Drop GENERATED_HEADERS dependency in rules.mak, since this  
> > > rebuilds all
> > > common objects after generating a target-specific header; add  
> > > dependency
> > > rules to Makefile and Makefile.target instead.
> > >
> > > v2:
> > > - Don't try to include /config.mak for user emulators
> > > - Changes to user object paths ("Quickfix for libuser.a drop")  
> > > were obsoleted
> > >  by "user_only: compile everything with -fpie" (Kirill A. Shutemov)
> >
> > Breaks build:
> >  CC    i386-softmmu/i386-dis.o
> > make[1]: *** No rule to make target `/loader.o', needed by `qemu'.   
> > Stop.
>
> I found out that completely removing the object directory and
> recreating it from scratch helps. This sucks bisectability-wise, is
> there any way to avoid it?

Sounds as if configure was not re-run and thus $(HWDIR) not set in  
config-target.mak. No idea why, more likely a general issue.
Do you have a way to reproduce? What about `make clean` or `make  
distclean`?

> There is still one problem, tools need config-host.h but the
> dependencies are not correct:
>  CC    qemu-nbd.o
> In file included from /src/qemu/qemu-nbd.c:19:
> /src/qemu/qemu-common.h:32:25: error: config-host.h: No such file or  
> directory

Fix coming up. Basically, $(GENERATED_HEADERS) were previously used on  
_all_ object files via rules.mak. That does not work when referencing  
objects from another Makefile, so the modelling needs to be done  
explicitly.

Andreas