Error "malformed-deb-archive newer compressed control.tar.xz" from Lintian on Ubuntu Xenial with cargo-deb > 1.28.0. about cargo-deb

[kornelski]

Good, at least it's not caused by the compression library :)

[ximon18]

@kornelski: Will you make a release containing the ec4e003 fix?

[ximon18]

@kornelski: I tried using commit ec4e003 and that worked!

[kornelski]

I've added --system-xz switch that replaces our xz2 library with xz command-line. Does this help?

[ximon18]

Thanks @kornelski, I'm not working today, I'll test it as soon as I can and get back to you.

[ximon18]

Hi @kornelski,

Unfortunately that doesn't seem to help. I updated our GitHub Actions workflow to install cargo-deb 1.35.0 and to use the --system-xz argument and Lintian still reports the error when running on Ubuntu Xenial.

Ximon

[ximon18]

Update: The work around of compiling without the lzma feature no longer works due to issue #43.

[ximon18]

With 1.34.2 I can compile without lzma support AND the Lintian checks pass on Xenial.

With 1.36.0 I can compile without lzma support but the resulting package the Lintian checks fail on Xenial.

With >1.36.0 I can't compile without default features (i.e. without lzma support) (due to #43) and so the Lintian checks fail on Xenial.

I haven't tested >1.34.2 && < 1.36.0.

[ximon18]

With >1.36.0 I can't compile without default features (i.e. without lzma support) (due to #43) and so the Lintian checks fail on Xenial.

The compilation issue was resolved in the 1.38.3 release with the fix of #43, but then I'm left with the issue that compiling without default features no longer solves the malformed-deb-archive error reported by Lintian on Xenial, i.e. I have the situation now that:

• With 1.34.2 I can compile without lzma support AND the Lintian checks pass on Xenial.
• With 1.36.0+ I can compile without lzma support but the resulting package the Lintian checks fail on Xenial.

E.g. see this failure on Xenial when using cargo-deb 1.38.3 which succeeds when using cargo-deb 1.34.2.

[kornelski]

Does Xenial support XZ-compressed control files at all?

e4764b6

[ximon18]

I don't know. What I do know is that disabling the lzma feature makes it work up until cargo-deb 1.34.2 but not later, and when I tried --system-xz a while ago (see above) that had no effect.

[kornelski]

I've googled, and there are plenty of bugs about Ubuntu not supporting LZMA in 16 and 18. So it seems the problem isn't in the lzma compressor, but the fact that an Ubuntu from 3 LTSes ego can't support dpkg format from the future.

[ximon18]

So, I'm confused. Disabling the lzma feature used to solve the problem. Was it then the case that that actually disabled something else than, or as well as, LZMA support, and this other thing is where the problem arises?

[kornelski]

The Cargo feature disables built-in Rust LZMA support, but in the meantime cargo-deb got a fallback to shell out to the xz command, so it always supports LZMA if the host operating system is able to compress LZMA.