draft-ietf-netmod-syslog-model-26.txt:
xym 0.4:
Extracting 'ietf-syslog@2018-03-15.yang'
   Removed 0 empty lines
Extracting 'example-vendor-syslog-types'
   Getting YANG file name from module name: example-vendor-syslog-types.yang


ietf-syslog@2018-03-15.yang:
pyang 1.7.8: pyang --verbose --ietf -p {libs} {model}:
# read ietf-syslog@2018-03-15.yang (CL)
# read /a/www/ietf-datatracker/6.100.0/env/share/yang/modules/ietf/ietf-inet-types.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-inet-types@2019-07-021.yang
# read /a/www/ietf-datatracker/6.100.0/env/share/yang/modules/ietf/ietf-interfaces.yang
# read /a/www/ietf-ftp/yang/rfcmod/ietf-interfaces@2018-02-20.yang
# read /a/www/ietf-datatracker/6.100.0/env/share/yang/modules/ietf/ietf-yang-types.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-yang-types@2019-07-21.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-tls-client@2019-07-02.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-tls-common@2019-07-02.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-keystore@2019-07-02.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-crypto-types@2019-07-02.yang
# read /a/www/ietf-datatracker/6.100.0/env/share/yang/modules/ietf/ietf-netconf-acm.yang
# read /a/www/ietf-ftp/yang/rfcmod/ietf-netconf-acm@2018-02-14.yang
ietf-syslog@2018-03-15.yang:761: error: grouping "private-key-grouping" not found in module ietf-keystore
ietf-syslog@2018-03-15.yang:762: error: grouping "certificate-grouping" not found in module ietf-keystore

yanglint 0.14.80: yanglint --verbose -p {rfclib} -p {draftlib} -p {tmplib} {model} -i:
err : Data model "ietf-truststore" not found.
err : Importing "ietf-truststore" module into "ietf-tls-client" failed.
err : Module "ietf-tls-client" parsing failed.
err : Importing "ietf-tls-client" module into "ietf-syslog" failed.
err : Module "ietf-syslog" parsing failed.