Deflate option causes mysterious log

[marvinborner]

In my peer/<name> file I've set deflate 9. Now, when running pon <name>, I get

deflate option value of 9 changed to 9 to avoid zlib bug

which is confusing.

[paulusmack]

What version of PPP are you using, and are you using a distro version, and have you made any local modifications?

The reason I'm asking is that this is the relevant line of the current upstream source:

        warn("deflate option value of %d changed to %d to avoid zlib bug",
             DEFLATE_MIN_SIZE, DEFLATE_MIN_WORKS);

DEFLATE_MIN_SIZE is defined to be 8 in include/linux/ppp-comp.h, and DEFLATE_MIN_WORKS is defined to be 9 in pppd/ccp.c. So I think the version you're using must have been modified from the upstream version.

[marvinborner]

Huh, interesting. I use Arch Linux with a normal linux kernel (6.10.7-arch1-1) with the default ppp installation from [extra].

$ pppd --help
ppp v2.5.1
Copyright (C) 1999-2022 Paul Mackerras, and others. All rights reserved.

It works regardless of the warning, so we may as well close this issue.