`uname -a' can't display revision

[KIRIYAMA Kazuhiko]

Hi all,

I've rebuild up to r351108 but `uname -a' can't display it's
revision number. 

admin at tbedfs:~ % uname -a
FreeBSD tbedfs 12.0-STABLE FreeBSD 12.0-STABLE GENERIC  amd64
admin at tbedfs:~ % 

And also compilation date and kernel path dropped. This is
same in releng:

admin at tbedfr:~ % uname -a
FreeBSD tbedfr 12.0-RELEASE-p9 FreeBSD 12.0-RELEASE-p9 GENERIC  amd64
admin at tbedfr:~ % 

But in 13.0-CURRENT:

admin at tbedfc:~ % uname -a
FreeBSD tbedfc 13.0-CURRENT FreeBSD 13.0-CURRENT r351108 GENERIC  amd64
admin at tbedfc:~ % 

revision number displayed. 

As far as uname(1), it's spec does not changed so far. Is
there any command to display revision number except uname ?

Best regards.
---
KIRIYAMA Kazuhiko