[U-Boot] Buildman Kconfig issue with consecutive builds

[Bin Meng]

Hi Frieder,

On Thu, Nov 7, 2019 at 9:28 PM Schrempf Frieder
<frieder.schrempf at kontron.de> wrote:
>
> Hi Bin,
>
> On 07.11.19 13:41, Bin Meng wrote:
> > Hi Schrempf,
> >
> > On Thu, Nov 7, 2019 at 12:17 AM Schrempf Frieder
> > <frieder.schrempf at kontron.de> wrote:
> >>
> >> Hi,
> >>
> >> I'm having some trouble using buildman to test the impact of some
> >> Kconfig cleanup patches ([1]).
> >>
> >> The patches introduce a new CONFIG_SPL_* option and I try to find out
> >> which defconfigs need to be fixed, by comparing build sizes.
> >>
> >> Now when I added a patch to fix a defconfig I noticed that buildman
> >> wouldn't report the expected size changes and upon looking more closely
> >> I found that the added Kconfig options are still missing in u-boot-spl.cfg.
> >>
> >> The strange thing is, that when I try to build only the last commit then
> >> the Kconfig options are there, which is why I suspect a bug in buildman
> >> not handling Kconfig changes correctly with consecutive builds.
> >>
> >> Can anyone have a look what is wrong or how I can debug this issue?
> >>
> >> The issue can be reproduced with the branch at [1], running:
> >>
> >> buildman -b spi_flash_kconfig_cleanup_3 --step 0 xilinx_zynqmp_virt
> >>
> >
> > Could you please add "-C" to the buildman command line and have a try?
>
> Indeed forcing the reconfig between the build steps with '-C' fixes the
> issue.
>
> Is it a known problem, that buildman doesn't handle Kconfig changes
> correctly without '-C' in some cases?

AFAIK, this is an intended design of calling buildman w/o '-C' to save
some build time.

Regards,
Bin