Here is a quick summary of the issue: 



The following function is failing: 
Note: Function used to remove a leading zero from string given to awk

Only in RHEL 8.0/8.1/8.2 ( gawk 4.2 ) 

$ echo 012345 | awk '{$0=int($0)}1'


Note: ( No data returned, just CR/LF ) 




The following alternatives do in fact seem to work under RHEL 8 ( gawk 4.2):

$  echo 012345 | awk '{print $0=int($0)}'
12345

$ echo 012345 | awk '{print int($0)}'
12345

$ echo 012345 | awk '{x=$0+0;print x}'
12345



Checking further into this the first alternative is closest to the original one, with one key difference: 


$ echo 012345 | awk '{$0=int($0)}1'
(CR/LF)                          ^----This 1 here seems to be a "shortcut" to print the output of the function,
                                        If any number other than 0 is in this position it evaluates as "true"
                                        It then prints the output, but in RHWL 8 ( gawk 4.2 ) it doesn't output anything.

$  echo 012345 | awk '{print $0=int($0)}'
12345                    ^------------If we explicitly use the "print" command to output the result of the int function, it works properly.
                                        Note: Even in RHEL 8 ( gawk 4.2 )

Thanks for the report, I've tried the gawk in Fedora (5.1.0) and it seems to work with the {$0=int($0)}1 pattern, so the problem is just with the RHEL-8 version, I will try the upstream commit you mentioned in your original message.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (gawk bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2021:1676