[Slackbuilds-users] several builds crashing looking for old libwebp

[Matteo Bernardini]

Il giorno mar 2 ott 2018 alle ore 12:36 David Melik
<davidnchmelik at gmail.com> ha scritto:
>
> On 10/2/18 2:35 AM, Matteo Bernardini wrote:
> > Il giorno mar 2 ott 2018 alle ore 11:19 David Melik
> > <dchmelik at gmail.com> ha scritto:
> >> NotepadQQ and KVIRC (though newly compiled) both immediately crash for
> >> not finding libwebp.so.6.  Well, that file is now at libwebp.so.7.0.2.
> >> King Beowulf told me (when I finally had to upgrade libwebp for BOINC
> >> instead of keeping an old one) this behaviour means libwebp is a runtime
> >> dependency (the SlackBuild maintainers must become aware of) and to link
> >> libwebp.so.6 to libwebp (which of course itself is a link to the
> >> 7.0.2.)  I did that, then both worked.  Previously the NotepadQQ
> >> maintainer said recompile/upgrade libwebp, then NotepadQQ... same thing
> >> happened. Well, the problem appears to be poor source code in both
> >> NotepadQQ and KVIRC (most likely) and/or SlackBuilds done wrong... or
> >> maybe the libwebp maintainer should become aware that some programs try
> >> to use a specific old version for some reason, and make a link in the
> >> SlackBuild.
> > if you upgrade a library to a newer major release with a shared
> > library version bump, like in your case, you should also rebuild
> > whatever links against it: I suspect the error you got is because you
> > have to rebuild qt5 and qt5-webkit (that you built against the old
> > libwebp in the first place).
>
> Okay; I had done that also but maybe in the wrong order... it's not
> clear again what built 'against' means rather than built 'from' (or
> 'depending on')...

if qt5 and qt5-webkit depends on libwebp you should build first
libwebp and then qt5 and then qt5-webkit (that depends on qt5), this
is necessary for a program/library using a dependency to link to it at
build-time.
I wrote "built against it" meaning "built linking to it", both forms
are often used on this mailing list, irc or the LQ forum.