Libudev as static library?

1

Hello!

I’m trying to build a static binary that depends on libudev.

Unfortunately nix-env -iA nixpkgs.pkgsStatic.libudev fails with:
error: p11-kit cannot be used as a static library

Is there a better way of doing this?

Thanks!

2

According to this comment, it does not make sense to build p11-kit statically. But looking at systemd expression, (libudev is an alias of systemd), the dependency is optional (systemd.override { withHomed = false; }). You can also try to use systemdMinimal, which disables most of the dependencies but still contains libudev. Edit: Actually, withHomed is disabled by default so p11-kit is likely pulled in by some dependency and it might be necessary to fix that first.

Generally, pkgsStatic, like anything, are maintained on a best-effort basis. If the build fails, the solution is to fix it in Nixpkgs and you can help with that.

3

Thanks, that makes things a bit clearer.

Statically building systemdMinimal (on nixpkgs-22.05pre333949.47b35f569e8) fails because of kbd:

% nix-env -iA nixpkgs.pkgsStatic.systemdMinimal
[...]
/nix/store/af96kdgvg090q1jwrndz9apx6lvnwfra-x86_64-unknown-linux-musl-binutils-2.35.2/bin/x86_64-unknown-linux-musl-ld: /nix/store/bzfz4fsayp7hjipbpylf86f13kp0lg00-linux-pam-static-x86_64-unknown-linux-musl-1.5.1/lib/libpam.a(pam_audit.o): in function `_pam_audit_writelog':
(.text+0xaa): undefined reference to `audit_log_acct_message'
/nix/store/af96kdgvg090q1jwrndz9apx6lvnwfra-x86_64-unknown-linux-musl-binutils-2.35.2/bin/x86_64-unknown-linux-musl-ld: /nix/store/bzfz4fsayp7hjipbpylf86f13kp0lg00-linux-pam-static-x86_64-unknown-linux-musl-1.5.1/lib/libpam.a(pam_audit.o): in function `_pam_audit_open':
(.text+0x175): undefined reference to `audit_open'
/nix/store/af96kdgvg090q1jwrndz9apx6lvnwfra-x86_64-unknown-linux-musl-binutils-2.35.2/bin/x86_64-unknown-linux-musl-ld: /nix/store/bzfz4fsayp7hjipbpylf86f13kp0lg00-linux-pam-static-x86_64-unknown-linux-musl-1.5.1/lib/libpam.a(pam_audit.o): in function `_pam_auditlog':
(.text+0x337): undefined reference to `audit_close'
/nix/store/af96kdgvg090q1jwrndz9apx6lvnwfra-x86_64-unknown-linux-musl-binutils-2.35.2/bin/x86_64-unknown-linux-musl-ld: /nix/store/bzfz4fsayp7hjipbpylf86f13kp0lg00-linux-pam-static-x86_64-unknown-linux-musl-1.5.1/lib/libpam.a(pam_audit.o): in function `pam_modutil_audit_write':
(.text+0x541): undefined reference to `audit_close'
[...]
error: builder for '/nix/store/7wdghkxrqgy47pfwqi8mcmgi03zsyr9y-kbd-static-x86_64-unknown-linux-musl-2.4.0.drv' failed with exit code 2
error: 1 dependencies of derivation '/nix/store/fbwz5d67kf2lrlg9lk63bdjj15q7f4gz-systemd-minimal-static-x86_64-unknown-linux-musl-249.5.drv' failed to build

The undefined reference audit_log_acct_message should be provided by the audit package, whose static version built fine:

% nm /nix/store/kasxd3y0cdn44vh7nd21nwhiaydfsq2j-audit-static-x86_64-unknown-linux-musl-2.8.5/lib/libaudit.a | grep audit_log_acct_message
0000000000000ac0 T audit_log_acct_message

audit is mentioned as a buildInput by systemd, but not by kbd. I tried adding it, but the error remains the same. Why can kbd (source) not see audit? I tried digging a bit and audit is indeed mentioned in NIX_LDFLAGS during kbd's build phase.

4

Please see #142472. systemd can’t be built statically because of symbol collisions, so unless we can find a resolution to that fundamental issue, none of the other failures are really relevant.

There’s also libudev-zero, which attempts to reimplement a subset of the udev API without requiring a daemon. It doesn’t currently build statically, but I’ve been working on a patch to enable that which I can prioritise since it seems like there are quite a few of us interested in static udev.

5

This particular issue should be fixed by #144749. It’s still in staging.

6

Also doesn’t pkgsStatic use musl for libc? systemd can’t be built with musl, even when dynamically linked.

7

It can in Nixpkgs! (And in other distros that use OpenEmbedded’s patches.)

8

Oh that’s new. Neat.

9

Oh! One more thing. Installing libraries with nix-env doesn’t work — it’s for installing programs, and even then it’s not very good at that compared to home-manager or NixOS. Libraries from Nixpkgs are only available in nix-shell and friends, or in Nix builds themselves. If you have more questions about using libraries with Nix, I recommend starting a new topic about that, where you’re more likely to reach people who can do a better job explaining than me. :slight_smile: