Re: problem with LOCAL_MODULES

On Fri, Aug 30, 2019 at 2:11 PM John Baldwin <jhb_at_freebsd.org> wrote:
>
> On 8/30/19 10:42 AM, Kyle Evans wrote:
> > On Fri, Aug 16, 2019 at 7:38 PM John Baldwin <jhb_at_freebsd.org> wrote:
> >>
> >> On 8/16/19 3:05 AM, Gary Jennejohn wrote:
> >>> I tried to build a kernel today and it failed in modules-all even
> >>> though I had LOCAL_MODULES="" in /etc/src.conf, as recommended by
> >>> jhb.
> >>>
> >>> That's wrong.  It has to be LOCAL_MODULES=, otherwise
> >>> /sys/conf/kern.post.mk seems to conclude that there should be a
> >>> module under /usr/local/sys/modules with the name "".
> >>
> >> I think this will permit both versions to work:
> >>
> >> Index: sys/conf/kern.post.mk
> >> ===================================================================
> >> --- kern.post.mk        (revision 351151)
> >> +++ kern.post.mk        (working copy)
> >> _at__at_ -76,6 +76,7 _at__at_ modules-${target}:
> >>         cd $S/modules; ${MKMODULESENV} ${MAKE} \
> >>             ${target:S/^reinstall$/install/:S/^clobber$/cleandir/}
> >>  .endif
> >> +.if !empty(LOCAL_MODULES)
> >>  .for module in ${LOCAL_MODULES}
> >>         _at_${ECHODIR} "===> ${module} (${target:S/^reinstall$/install/:S/^clobber$/cleandir/})"
> >>         _at_cd ${LOCAL_MODULES_DIR}/${module}; ${MKMODULESENV} ${MAKE} \
> >> _at__at_ -83,6 +84,7 _at__at_ modules-${target}:
> >>             ${target:S/^reinstall$/install/:S/^clobber$/cleandir/}
> >>  .endfor
> >>  .endif
> >> +.endif
> >>  .endfor
> >>
> >>  # Handle ports (as defined by the user) that build kernel modules
> >>
> >
> > I think I'd like to see this with !empty(LOCAL_MODULES) &&
> > EXISTS(${LOCAL_MODULES_DIR}) or maybe just the latter condition to
> > prevent accidental foot-shooting... I was testing a problem with doing
> > this stuff in a poudriere build for swills_at_ and set LOCAL_MODULES=""
> > only to get an error because LOCAL_MODULES_DIR doesn't yet exist on
> > the machine I was testing with -- which we can trivially avoid.
>
> Did this work for you?  Gary said in a followup that it didn't work,
> so that's why I hadn't committed it.
>

Hmm... I went back and tested his exact scenario, and no-
LOCAL_MODULES isn't empty at this point because word processing that
leaves us with an empty string hasn't yet been done. An .if
!empty(module) inside the loop is much happier- I'm not seeing any
modifiers that would give us the behavior we wanted for figuring this
out before entering the loop.