[...]

building SRPM using: cd rpm/packages; nice -n 0 ./builder -nu -nm --nodeps --http --define '_tld_builder 1' -bs  -r HEAD  -Tp auto/ti/ -tt   libwacom.spec 2>&1
Cloning into 'libwacom'...
187b4c0aa6f820ceabd54c017314ec311c475916
Already on 'master'
Your branch is up to date with 'origin/master'.
Already up to date.
Available branches: master
Searching for tag auto/ti/libwacom-0.29-1...
Searching for tag auto/ti/libwacom-0_29-1...
--2018-08-31 21:24:12--  http://distfiles.pld-linux.org/distfiles/by-md5/3/a/3a6b614b57518b25a102dcd9e51d6681/libwacom-0.29.tar.bz2
Resolving distfiles.pld-linux.org (distfiles.pld-linux.org)... 193.239.45.41
Connecting to distfiles.pld-linux.org (distfiles.pld-linux.org)|193.239.45.41|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 495549 (484K) [application/x-bzip2]
Saving to: 'libwacom-0.29.tar.bz2'
     0K .......... .......... .......... .......... .......... 10% 1.22M 0s
    50K .......... .......... .......... .......... .......... 20% 2.43M 0s
   100K .......... .......... .......... .......... .......... 30% 71.1M 0s
   150K .......... .......... .......... .......... .......... 41% 82.1M 0s
   200K .......... .......... .......... .......... .......... 51% 2.59M 0s
   250K .......... .......... .......... .......... .......... 61% 78.2M 0s
   300K .......... .......... .......... .......... .......... 72% 50.2M 0s
   350K .......... .......... .......... .......... .......... 82%  200M 0s
   400K .......... .......... .......... .......... .......... 92% 2.67M 0s
   450K .......... .......... .......... ...                  100%  450M=0.1s
2018-08-31 21:24:12 (4.71 MB/s) - 'libwacom-0.29.tar.bz2' saved [495549/495549]
Building target platforms: i686-linux
Wrote: /home/users/builder/rpm/SRPMS/libwacom-0.29-1.src.rpm
exit status 0
Tagging with prefix: auto/ti/
Already on 'master'
Writing git revision for tag auto/ti/libwacom-0.29-1
error: Macro %_builddir has empty body
error: Macro %_builddir has empty body
Executing(--clean): env -i TMP=/home/users/builder/tmp HOME=/home/users/builder PATH=/bin:/usr/bin:/usr/sbin:/sbin:/usr/X11R6/bin TMPDIR=/home/users/builder/tmp  /bin/sh -e /home/users/builder/tmp/rpm-tmp.89918
+ umask 022
+ cd /home/users/builder/rpm/BUILD
+ rm -rf libwacom-0.29
Begin-TLD-Builder-Info
Build-Time: user:0.55s sys:0.05s real:2.11s (faults io:0 non-io:93696)
Files queued for ftp:
    500573 libwacom-0.29-1.src.rpm
       185 libwacom-0.29-1.src.rpm.uploadinfo
End-TLD-Builder-Info