What's gawk 5.1.1?

[Arkadiusz Drabczyk]

In gawk.info it says:

"Prior to version 5.1.1 of 'gawk', as an accident of the
implementation, '$0' and the fields retained any previous values they
had in 'BEGINFILE' rules.  Starting with version 5.1.1, '$0' and the
fields are cleared, since no record has been read yet from the file
that is about to be processed."

And indeed, it works like that with gawk built from today's master but
not with gawk provided by Slackware -current which is the OS that I
use but the thing is that both of them report to be 5.1.0:

master:

./gawk --version | head -2
GNU Awk 5.1.0, API: 3.1 (GNU MPFR 4.1.0, GNU MP 6.2.0)
Copyright (C) 1989, 1991-2020 Free Software Foundation.

Slackware:

$ gawk --version | head -2
GNU Awk 5.1.0, API: 3.0 (GNU MPFR 4.1.0, GNU MP 6.2.0)
Copyright (C) 1989, 1991-2020 Free Software Foundation.

The string 5.1.1 only appears in several places in the source code
tree:

[ja:~/awk/gawk] master+* ± ag '5\.1\.1' -l
doc/ChangeLog
doc/gawktexi.in
doc/it/gawktexi.in
doc/gawk.info
doc/gawk.texi
doc/gawk.ps
NEWS

But there is PACKAGE_STRING='GNU Awk 5.1.0' in ./configure. Can you
please clear this up?

-- 
Arkadiusz Drabczyk <arkadiusz@drabczyk.org>