Peter Maydell <peter.mayd...@linaro.org> wrote: > On 17 July 2018 at 18:05, Juan Quintela <quint...@redhat.com> wrote: >> Daniel P. Berrangé <berra...@redhat.com> wrote: >>> On Tue, Jul 17, 2018 at 01:33:38PM +0200, Juan Quintela wrote: >>>> If you don't want to compile everything, you configure >>>> config-devices.mak. And then make clean remove it, and make will >>>> create a default one without your configuration. Fix it by not >>>> removing it. >>>> >>>> Signed-off-by: Juan Quintela <quint...@redhat.com> >>>> --- >>>> Makefile | 2 +- >>>> 1 file changed, 1 insertion(+), 1 deletion(-) >>>> >>>> diff --git a/Makefile b/Makefile >>>> index 2da686be33..2ffbcde323 100644 >>>> --- a/Makefile >>>> +++ b/Makefile >>>> @@ -751,7 +751,7 @@ clean: >>>> if test -d $$d; then $(MAKE) -C $$d $@ || exit 1; fi; \ >>>> rm -f $$d/qemu-options.def; \ >>>> done >>>> - rm -f $(SUBDIR_DEVICES_MAK) config-all-devices.mak >>>> + rm -f config-all-devices.mak >>>> >>>> VERSION ?= $(shell cat VERSION) >>> >>> This feels wrong to me. If 'make' is creating config-devices.mak, then >>> either 'make clean' or 'make distclean' must remove it. So if you remove >>> it here, it should be added to distclean instead. >> >> I can agree with putting it on distclean. >> >> make don't put it there if it is already there. My use case is that I >> have several build trees from the same source three: >> >> - x86_64-softmmu with minimal set of devices (the ones that I use) >> - x86_64-softmmu with everything under the sun >> - everything that can be compiled in in fedora >> >> for the 1st case, I am interested that it is fast, so I edit the >> x86_64-softmmu/config-device.mak. But if I do a make clean for any >> reason, I lost my changes. > > I think the problem here is that we're confused about whether > config-devices.mak should be a user-editable file or just > part of our build process. Personally I think we should go > for the latter, ie if there are useful use cases that > currently you need to edit the file to achieve, we should > provide a better mechanism for doing them.
I agree with the better mechanism, but until them this is the only way to "choose" what devices to compile in. It is a very bad mechanism, but it is the only one that we have right now. On a general level, for devices that are quite well isolated, it works quite well. But for the rest of the things, it is kind of messy. - No dependencies So, if you look at the generated x86_64-softmmu/config-devices,mak, you can see that we define CONFIG_SCSI=y at least three times - No way to show that dependencies at the C level, so we can only compile in/out at the file level - simple things like pc-speaker, msmouse or vmport, you can't compile out, because they are created by code, not by qom/configuration/whatever. On the other hand, sometimes it looks like I am the only user that use this. The original reason for this was to be able to compile out drivers that downstream don't care about. There were a couple of intents to integrate with something like kernel kconfig, but I think that we never end integrating anything from there. Later, Juan.
