BUG: do not use the first field avalaible as label if no field is provided

13 jobs for !515 with field_get_value_assert in 57 minutes and 25 seconds (queued for 3 seconds)
detached
Status Job ID Name Coverage
  Precheck
passed #6767
fast-build

00:06:38

 
  Prepare
passed #6769
centos-superbuild-prepare

00:14:08

passed #6770
macos
macos-superbuild-prepare

00:01:05

passed #6768
ubuntu-superbuild-prepare

00:01:12

 
  Build
passed #6773
centos-superbuild-build

00:34:11

passed #6771
debian-build

00:24:38

passed #6774
macos
macos-superbuild-build

00:17:46

passed #6772
ubuntu-superbuild-build

00:36:35

 
  External
passed cdash:debian-unstable-gcc

passed cdash:otb-centos-superbuild-base

passed cdash:otb-macos-superbuild

passed cdash:ubuntu-18.04-fast

passed cdash:ubuntu-18.04-llvm-xdk