Re: [Qemu-devel] [PATCH] 9p: simplify source file selection

[Paolo Bonzini]

On 25/07/19 12:21, Peter Maydell wrote:
>>  # Lots of the fsdev/9pcode is pulled in by vl.c via qemu_fsdev_add.
>>  # only pull in the actual 9p backend if we also enabled virtio or xen.
>> -ifeq ($(call land,$(CONFIG_VIRTFS),$(call 
>> lor,$(CONFIG_VIRTIO_9P),$(CONFIG_XEN))),y)
>> +ifeq ($(CONFIG_FSDEV_9P),y)
>>  common-obj-y = qemu-fsdev.o 9p-marshal.o 9p-iov-marshal.o
>>  else
>>  common-obj-y = qemu-fsdev-dummy.o
>
> Maybe we should update the comment here somehow too now?

The comment is still accurate, just a bit low level. :)

> Patch definitely looks like a good idea, though -- those
> nested land/lor calls are pretty ugly :-)

Yeah, FWIW this patch came out of Meson conversion, where the sourceset
mechanism supports "and", "nand" and "or" very well but has issues with
"nor".  While I'm open to adding "nor" if it is really needed, it seems
to me that in general we should not transpose our Make mess to Meson,
and rely on Kconfig as the better tool for this kind of job.

(For a Meson update, see https://wiki.qemu.org/Features/Meson).

Paolo