The files
zic.c zdump.c tzfile.h private.h tzselect.ksh version
come from the tzcode package by Arthur David Olson et.al.
The 'version' file specifies which tzcode version was used.
The files
africa antarctica asia australasia europe
northamerica southamerica pacificnew etcetera factory
backward systemv solar87 solar88 solar89
iso3166.tab zone.tab leapseconds yearistype
come from the tzdata package by Arthur David Olson et.al.
except that its 'yearistype.sh' file is renamed to 'yearistype'.
These tzdata files were taken from tzdata 2009i and have not been
updated since, as they do not affect glibc installation and are
present only for regression testing.
Please also see: https://sourceware.org/glibc/wiki/SharedSourceFiles
These packages may be found at https://ftp.iana.org/tz/releases/.
Commentary should be addressed to tz@iana.org.
The subdirectory testdata contains manually edited data files for
regression testing purposes.