Dear Maintainer,

After upgrading to glibc 2.41-12+deb13u1 (Debian 13.3 point release on
January 10, 2026), all KDE/Qt applications experience severe startup
delays of 1-3 seconds. Previously these applications started instantly.

What led up to the situation:
System was updated with 'apt upgrade' which included the glibc update
from the 13.3 point release.

What exactly did you do:
Tested multiple terminals and applications:
- Konsole: 2-3 second startup delay
- Alacritty: 1-2 second startup delay
- Other Qt/KDE applications show similar slowdown
- Non-Qt applications (xterm) start instantly

What was the outcome:
All Qt/KDE applications now have significant startup delays making the
system feel sluggish and unresponsive.

What outcome did you expect:
Applications should start instantly as they did before the update.

Additional information:
- Tested on both kernel 6.12.57 and 6.12.63 - issue persists on both
- GLIBC_TUNABLES=glibc.rtld.execstack=1 workaround does NOT resolve the issue
- Intel Iris Xe Graphics (amd64), KDE Plasma on Wayland
- This represents a significant usability regression for a stable release

Hi,

Have you been able to confirm the issue actually comes from this new
glibc version? For instance you can try downgrading it to version
2.41-12 and check it solves the issue.

I have tried to reproduce the issue, but I haven't been able to so far.
Also looking at the change introduced in this new version, I haven't
been able to find an obvious culprit in the commit backported in this
version.

Could you please try to run any of the software having an issue under
strace and share the output? That could give a hint at what is wrong.
You might want to use the -tt option to get timestamp and the -o option
to save the log.

Regards
Aurelien

Hi,
Here are the strace logs you requested; ran on Konsole, Alacritty, and
xterm.

Logs attached.

Regards and many thanks
chris

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