Sent: Friday, January 31, 2020 at 5:19 AM
From: "Alan Feuerbacher via blfs-support" 
<[email protected]>
To: [email protected]
Cc: "Alan Feuerbacher" <[email protected]>
Subject: Re: [blfs-support] glibc-2.30 No Longer Builds, After Updating to 
Linux-5.5.0

On 1/29/2020 8:52 PM, Ken Moffat via blfs-support wrote:
On Wed, Jan 29, 2020 at 07:00:18PM -0700, Alan Feuerbacher via blfs-support 
wrote:
I'm building the development version of systemd.

After updating various programs listed in the Changelogs for LFS and BLFS, I
left linux-5.5 for last. I had upgraded to linux-5.4.13 a few days ago,
without trouble. Keeping in mind that glibc-2.30 depends on the linux
headers, as stated in the LFS book:
 
[snip]

Alan,

If I've parsed your mail correctly, you are updating glibc on a
completed system.  
Right. Completed, at least, to the point where KDE etc. can be installed.
If I've misparsed that, I'm sure I'll find out
when I start my next test build.

Very few people here update glibc in a running LFS system.  Unlike
binary distros, we don't ship a new build of glibc when the kernel
headers change (or, indeed, at all - we don't ship any binaries).
That makes sense to me for the stable versions of LFS, but I thought the 
purpose of the development versions was for someone like me to install new 
packages as they come along.
I myself have rebuilt glibc a couple of times in running systems:
once was for an awkard issue related to sound, many years ago, and
the more recent set of builds were when a vulnerability in glibc
became known - again, several years ago.

For the plain rebuild there was a very small change so I rebuilt the
exact same version of glibc agaisnt the existing headers.  For the
more involved vulnerability fixes I _think_ I backported the fix to
the versions I cared about, and rebuilt them in a similar way.
I don't understand what that means.
What I had to do in each case was force a reboot immediately after
installing the revised glibc (and I think I needed to use the power
button).  
So rebuilding glibc sort of clobbered your system? As I said, I rebuilt 
glibc-2.30 using headers from linux-5.4.8 and again with linux-5.4.13, and the 
system ran fine. At least, I *think* it did. Only when I tried with linux-5.5.0 
did things go south.
For the wider set of vulnerability fixes to past versions
my memory says that one or more of the older versions I was still
trying to keep usable failed (although with compilation errors, not
a loop), and at that point I stopped trying to keep them usable - I
think they were already several verisons behind current LFS at that
time.

TLDR; Don't update glibc on a running LFS system, or if you have to
(vulnerability fixes) keep the same verison, same headers, and
reboot as soon as it is installed - even then, no guarantees that it
will be usable.
I'll remember that.
Addendum: You are probably the only person rebuilding *everything*
in the "Rolling Release" model - I think most of us take the view
that while we will rebuild to fix vulnerabilities, or to fix bugs
which affect our own use of the system, rebuilding everything is not
for us.  I know some people never rebuild anything on a completed
system, I cannot recommend that but rebuilding everything is a waste
of your time and electricity.  OTOH I try to build new systems when
we are coming up to releasing the next version of the books, and in
between times for testing, so my systems only have a few months of
being in currnet use, and then the versions that match book releases
will typically get semi-maintained for a year or so (used to be
longer, but too many problems in updating e.g. firefox on older
toolchains).
And here I thought y'all kept up to date on all systems with your automatic 
build tools, kind of the way active distributions like Fedora do for you 
automatically. :-)
The reasons I've wanted to install updated packages as they come along are 
partly my desire to keep *all* software up to date, and partly because doing so 
tends to teach me things that I would not learn otherwise. After all, on an 
introductory LFS page it's stated:
<< LFS teaches people how a Linux system works internally
Building LFS teaches you about all that makes Linux tick, how things work 
together and depend on each other. And most importantly, how to customize it to 
your own tastes and needs. >>
There's nothing like solving problems that teaches you so well about how 
systems tick.
As for installing updated packages, the page "Read the Linux From Scratch Book 
Online" states:
<< Current Development
This is the LFS systemd Book in its current development state. Whilst it may 
provide more features and updated upstream packages than the stable book, it is 
more prone to bugs and security vulnerabilities. >>
The BLFS book says essentially the same thing:
<< Current Development
This is the BLFS systemd Book in its current development state. Changes can 
happen that break the build of some packages temporarily. Since this version of 
the book is in constant change, there is no separate errata. >>
To me these statements suggest that the purpose of making development versions 
available is to allow updating packages as they come along; otherwise one would 
want to stick with a Stable version. Am I misinterpreting that?
What I vaguely have in mind, not knowing any better, is that by upgrading the 
current development version as changes come along, my system will gradually 
morph into what will become the Stable version for the next LFS go-around. In 
March, perhaps?
I guess what I'm trying to do is a form of package management. Since I've 
barely gotten LFS installed as a working system and not yet sorted out many 
issues, I've not really considered package management in any detail. Anyway, 
here's what the LFS book says in section "6.3.1 Upgrade Issues":
<< If Glibc needs to be upgraded to a newer version, (e.g. from glibc-2.19 to 
glibc-2.20), it is safer to rebuild LFS. Though you may be able to rebuild all 
the packages in their dependency order, we do not recommend it. >>
Clear enough, but that says nothing about my problem at hand: what should one 
do when the Linux kernel is updated but Glibc remains the same?
As I understand the operation of Linux's dynamic libraries, one can change the 
underlying software without issues as long as the name of the dynamic library 
remains the same. Indeed, that's the purpose of dynamic libraries.
If that's the case, why would updates to packages be a problem as long as the 
names of the dynamic libraries remained the same?
Anyway, since beginning my LFS installation in late December I've successfully 
updated the kernel several times: 5.4.6 -> 5.4.8 -> 5.4.13 had no issues that I 
can see. But going to 5.5.0 seems to have broken something, but I don't know 
what.
So for now, since the 5.4.13 installation seems mostly to work, I'll stop 
trying to update to 5.5.0. I still have the issue with Fluxbox, though: when I 
run configure, I get:
<< configure error: Your libstdc++ doesn't have the sstream or strstream 
classes >>
To test things further, I've built several more packages successfully:
openbox
librep
rep-gtk
sawfish
So I'll just move on for now, hoping I haven't broken something irreparably.
Thanks for your help!
Alan
 

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Hello,

I am going to say this because I am now PISSED OFF.

Anyone who posts on multiple failures to install/upgrade software has no place 
using linux.  If you are unable to comprehend the English language, and read 
what has been written and provided, do not expect people to hold your hand 
constantly.  You are a waste of space on this list.  No one is here to teach 
you.  Learn for yourself by using google and actually getting a firm grip on 
the basics of linux.  You do NOT have such knowledge.  Format your computer and 
go back to WINDOWS.

Christopher.
 
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