glibc 2.42 breaks WSL 1 distros

[g3nsvrv]

Windows Version

Windows 10 [Version 10.0.19045.6093]

WSL Version

2.5.10.0

Are you using WSL 1 or WSL 2?

• [ ] WSL 2
• [x] WSL 1

Kernel Version

idk, latest, i cannot access it anymore.

Distro Version

ArchLinux latest

Other Software

No response

Repro Steps

1. wsl --uninstall
2. wsl --update
3. Cloud be any of these 1.On official image:
   1. wsl --install --enable-wsl1 archlinux
   2. Terminal works, but without PS1
   3. Opening a new terminal just crash
4. On yuk7/ArchWSL 1. wsl --set-default-version 1 2. Install Certificate 3. Install AppX 4. Same result as the official image

Expected Behavior

Just work like always

Actual Behavior

The previous version worked just fine, but wsl got updated yesterday and everything crashed.

wsl -d arch
wsl: Processing /etc/fstab with mount -a failed.
wsl: Failed to mount C:\, see dmesg for more details.
wsl: Failed to mount D:\, see dmesg for more details.
wsl: Failed to translate 'C:\Users\username'
wsl: Failed to translate 'C:\Program Files (x86)\Common Files\Oracle\Java\java8path'
wsl: Failed to translate 'C:\Program Files (x86)\Common Files\Oracle\Java\javapath'
wsl: Failed to translate 'C:\Program Files (x86)\VMware\VMware Workstation\bin\'
wsl: Failed to translate 'c:\windows\system32'
wsl: Failed to translate 'c:\windows'
wsl: Failed to translate 'c:\windows\system32\wbem'
wsl: Failed to translate 'c:\windows\system32\windowspowershell\v1.0\'
wsl: Failed to translate 'c:\windows\system32\openssh\'
wsl: Failed to translate 'c:\program files\dotnet\'
wsl: Failed to translate 'C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common'
wsl: Failed to translate 'C:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\'
wsl: Failed to translate 'C:\Program Files\Microsoft VS Code\bin'
wsl: Failed to translate 'C:\Users\username\AppData\Local\Microsoft\WindowsApps'
wsl: Failed to translate 'C:\Users\username\AppData\Local\Programs\Microsoft VS Code\bin'
<3>WSL (11 - SessionLeader) ERROR: operator():519: getpwuid(0) failed 2
<3>WSL (11 - SessionLeader) ERROR: CreateProcessCommon:735: execvpe(/bin/sh) failed: No such file or directory

Diagnostic Logs

WslLogs-2025-08-11_13-07-43.zip

[github-actions[bot]]

Diagnostic information

Detected appx version: 2.5.10.0

[g3nsvrv]

im not sure at this point if this is an issue with arch or wsl, because it happens right when you do a full system upgrade:

Packages (83) audit-4.0.5-1  bash-5.3.3-2  ca-certificates-mozilla-3.114-1  coreutils-9.7-1  cryptsetup-2.8.0-1
              curl-8.15.0-1  dbus-1.16.2-1  dbus-broker-37-2  dbus-broker-units-37-2  dbus-units-37-2
              device-mapper-2.03.34-1  e2fsprogs-1.47.3-1  expat-2.7.1-1  file-5.46-5  filesystem-2025.05.03-1
              findutils-4.10.0-3  gawk-5.3.2-1  gcc-libs-15.1.1+r500+gb1b8d8ce3eea-1  gdbm-1.25-1  gettext-0.26-1
              glib2-2.84.3-1  glibc-2.42+r3+gbc13db739377-1  gnupg-2.4.8-1  gnutls-3.8.10-1  gpgme-2.0.0-1  grep-3.12-2
              gzip-1.14-2  hwdata-0.397-1  iana-etc-20250612-1  iproute2-6.16.0-2  iptables-1:1.8.11-2
              iputils-20250605-1  json-c-0.18-2  kbd-2.8.0-1  kmod-34.2-1  krb5-1.21.3-2  leancrypto-1.5.1-1
              less-1:679-1  libarchive-3.8.1-1  libbpf-1.5.1-1  libcap-2.76-1  libelf-0.193-3  libffi-3.5.1-1
              libgcrypt-1.11.1-1  libgpg-error-1.55-1  libksba-1.6.7-2  libldap-2.6.10-2  libnftnl-1.3.0-1
              libnghttp2-1.66.0-1  libnghttp3-1.11.0-1  libpcap-1.10.5-3  libseccomp-2.5.6-1  libsecret-0.21.7-1
              libsysprof-capture-48.0-6  libtirpc-1.3.6-2  libusb-1.0.29-1  libxml2-2.14.5-1  linux-api-headers-6.16-1
              mpfr-4.2.2-1  nano-8.5-1  ncurses-6.5-4  nettle-3.10.2-1  openssl-3.5.2-1  pacman-7.0.0.r6.gc685ae6-6
              pacman-mirrorlist-20250702-2  pam-1.7.1-1  pambase-20250719-1  pciutils-3.14.0-1  pinentry-1.3.2-1
              procps-ng-4.0.5-3  readline-8.3.001-1  shadow-4.18.0-1  sqlite-3.50.4-1  sudo-1.9.17.p1-1
              systemd-257.8-2  systemd-libs-257.8-2  systemd-sysvcompat-257.8-2  tzdata-2025b-1  util-linux-2.41.1-1
              util-linux-libs-2.41.1-1  vim-9.1.1623-1  vim-runtime-9.1.1623-1  xz-5.8.1-1

[g3nsvrv]

ok, I tried to upgrade each one manually, and it seems that glibc-2.42+r3+gbc13db739377-1 broke the whole thing... nice.

[g3nsvrv]

rolling back to glibc-2.41+r48+g5cb575ca9a3d-1-x86_64 resolved the issue temporarily

[g3nsvrv]

ok, I have upgraded wsl to the latest version once again using wsl --update and everything works fine.

In short, there is an issue with:

• WSL 1
• glibc 2.42

This combination broke the terminal; you can run commands but the prompt (PS1) does not show up, neither colors.

[g3nsvrv]

yep, indeed. I tried once again on a vm that I have that uses the same version of windows, but everything is clean and by default, and indeed, after upgrading all packages it broke, but rolling back glibc to version 2.41 everything returns back to normal. bruh.

In case that someone wants the binary (from official archive.archlinux.org):

https://archive.archlinux.org/repos/2025/07/01/core/os/x86_64/glibc-2.41%2Br48%2Bg5cb575ca9a3d-1-x86_64.pkg.tar.zst

[benhillis]

Changed title because the package update is not to blame

[github-actions[bot]]

Diagnostic information

Detected appx version: 2.5.10.0

[Marc-Aldorasi-Imprivata]

This sounds like #2595

[g3nsvrv]

This sounds like #2595

@Marc-Aldorasi-Imprivata yes and no. it seems that issue mutated a lot, which lead into the glibc issue, but the original issue was something else.

[GB609]

I have the exact same issue. Terminal started to behave strangely after an update, but i wasn't sure whether it was caused by a windows or an arch linux update. I did manage to at least get PS1 to work by deliberately stepping into a bash -i subshell, but still had issues with most non-letter keys (and key combinations). Passwords also were plain visible.

Can confirm that it works again with glib 2.41.

[fragtion]

Not just arch - glibc 2.42 affecting Ubuntu 25.10 (Questing Quokka) on WSL1. rolled back to 2.41 which saved the terminal, but now other packages that depend on 2.42 are failing too, so this situation is obviously quite serious and probably ought to be treated as such

[rtiangha]

I thought I was the only one experiencing this. Running Arch in WSL1. Downgrading to glibc 2.41 helped, but now as more and more Arch packages are being built against glibc 2.42, I had to upgrade.

Note that (at least on my setup), the shell still works even though the terminal looks blank. You can type commands (like ls) and stuff appears. Passwords aren't hidden though; they appear in plain text when typed in where they should be hidden instead and the text that appears before the prompt displaying your username doesn't render (which is why the terminal appears to be blank or hung).

Edit: Using this workaround seems to have made my terminal usable again. But unknown if there are other hidden issues running glibc 2.42 on this set up with WSL1.

[edo9300]

Experiencing the same issue here with the same "resolution" of using that workaround, but i guess the issue here should be raised within glibc itself in case? i don't think ms is going to update wsl1 anytime soon, especially on old windows editions

[g3nsvrv]

Experiencing the same issue here with the same "resolution" of using that workaround, but i guess the issue here should be raised within glibc itself in case? i don't think ms is going to update wsl1 anytime soon, especially on old windows editions

My solution was moving to Linux kek. Win10 is dead anyways

[OneBlue]

Thank you all for reporting this !

To give an update, the issue is indeed #2595. WSL1 currently doesn't implement TCGETS2, which causes packages built on glibc 2.42 to fail in various places.

We have merged a WSL1 change that implement that IOCTL alongside TCSETSW2, TCSETSF2 and TCSETS2. The change will ship via the Windows Insider builds.

I'll update this issue once the fix is available.

[edo9300]

Thank you all for reporting this !

To give an update, the issue is indeed #2595. WSL1 currently doesn't implement TCGETS2, which causes packages built on glibc 2.42 to fail in various places.

We have merged a WSL1 change that implement that IOCTL alongside TCSETSW2, TCSETSF2 and TCSETS2. The change will ship via the Windows Insider builds.

I'll update this issue once the fix is available.

Which windows channels will receive this fix in future? Will it only be available on windows 11?

[g3nsvrv]

Thank you all for reporting this !

To give an update, the issue is indeed #2595. WSL1 currently doesn't implement TCGETS2, which causes packages built on glibc 2.42 to fail in various places.

We have merged a WSL1 change that implement that IOCTL alongside TCSETSW2, TCSETSF2 and TCSETS2. The change will ship via the Windows Insider builds.

I'll update this issue once the fix is available.

Thanks for taking this. @OneBlue Can you confirm if this will be available on windows 10 LTSC?