[libvirt] [PATCH v3] nwfilter: fix loadable module support

[Matthias Bolte]

2010/6/22 Daniel P. Berrange <berrange at redhat.com>:
> On Tue, Jun 22, 2010 at 12:48:37PM +0200, Matthias Bolte wrote:
>> 2010/6/22 Daniel P. Berrange <berrange at redhat.com>:
>> > On Mon, Jun 21, 2010 at 02:27:36PM -0400, Stefan Berger wrote:
>> >> diff --git a/src/Makefile.am b/src/Makefile.am
>> >> index 5109302..e553f35 100644
>> >> --- a/src/Makefile.am
>> >> +++ b/src/Makefile.am
>> >> @@ -1001,7 +1001,7 @@ libvirt_la_LDFLAGS =
>> >> $(VERSION_SCRIPT_FLAGS)$(LIBVIRT_SYMB
>> >>                     $(CYGWIN_EXTRA_LDFLAGS) $(MINGW_EXTRA_LDFLAGS)
>> >>  libvirt_la_BUILT_LIBADD += ../gnulib/lib/libgnu.la
>> >>  libvirt_la_LIBADD += $(LIBXML_LIBS) \
>> >> -                   $(LIBPCAP_LIBS) $(LIBNL_LIBS) \
>> >> +                   $(LIBPCAP_LIBS) $(LIBNL_LIBS) $(GNUTLS_LIBS) \
>> >>                     $(DRIVER_MODULE_LIBS) \
>> >>                     $(CYGWIN_EXTRA_LIBADD)
>> >>  libvirt_la_CFLAGS = $(COVERAGE_CFLAGS) -DIN_LIBVIRT
>> >
>> > I think that one needs to be against libvirt_driver_la_CFLAGS instead.
>> > since that's where the source file using gnutls is.
>> >
>> > Regards,
>> > Daniel
>> >
>>
>> I think the problem Stefan tries to fix here is this one while linking
>> virsh. The calls to gcry_check_version and gcry_control are in
>> libvirt.c itself.
>
> The libvirt.c file is compiled into libvirt_driver.la, which in
> turn links to libvirt.la. The libraries should always be linked
> directly to the module which uses them. There are no .c files
> listed directly against libvirt.la, hence there should never be
> any need for libraries to link directly against libvirt.la. The
> final libvirt.la will inherit linkage for all the sub-libraries
> The only real exceptions to this should be LIBXML since that is
> used in pretty much every module and its a waste of time to have
> it duplicated it in all places, and the cygwin bits.

Ah, okay. My fault, I didn't look it up properly.

>>   CCLD   virsh
>> ../src/.libs/libvirt.so: undefined reference to `gcry_check_version'
>> ../src/.libs/libvirt.so: undefined reference to `gcry_control'
>>
>> Therefore, this patch adds GnuTLS to libvirt_la_{LIBADD|CFLAGS}. It
>> also adds a missing dependency for the statstest.
>
> statstest links to libvirt_test.la which links to libvirt_driver.la
> so it will inherit the link to gnutls still.
>
> We should not need to add any libraries directly to libvirt_la_LIBADD,
> always to one of the other modules first.
>
>> diff --git a/src/Makefile.am b/src/Makefile.am
>> index 5109302..eb93727 100644
>> --- a/src/Makefile.am
>> +++ b/src/Makefile.am
>> @@ -1001,10 +1002,10 @@ libvirt_la_LDFLAGS =
>> $(VERSION_SCRIPT_FLAGS)$(LIBVIRT_SYMBOL_FILE) \
>>                     $(CYGWIN_EXTRA_LDFLAGS) $(MINGW_EXTRA_LDFLAGS)
>>  libvirt_la_BUILT_LIBADD += ../gnulib/lib/libgnu.la
>>  libvirt_la_LIBADD += $(LIBXML_LIBS) \
>> -                   $(LIBPCAP_LIBS) $(LIBNL_LIBS) \
>> +                   $(LIBPCAP_LIBS) $(LIBNL_LIBS) $(GNUTLS_LIBS) \
>
> These two previous additions of LIBPCAP and LIBNL are both wrong
> too. They should be linking to libvirt_driver_nwfilter.la instead.
>

Okay. I'll fix that too.

Matthias