Image Build Fails on Podman

[Alexhuszagh]

Checklist

• I've looked through the issues and pull requests for similar reports

Describe your issue

Currently, attempting to build an image for Podman fails, producing the following error:

$ cargo build-docker-image $target --engine podman                                                                                                                                                  
    Finished dev [unoptimized + debuginfo] target(s) in 0.07s
     Running `target/debug/xtask build-docker-image aarch64-linux-android --engine podman`
[cross] note: Build aarch64-linux-android for x86_64-unknown-linux-gnu
Error: unable to parse value provided `` to --cache-from: invalid repo "type=registry,ref=ghcr.io/cross-rs/aarch64-linux-android:main": must contain registry and repository: invalid reference format
Error: 
   0: `podman buildx build --platform linux/amd64 --load --pull --cache-from 'type=registry,ref=ghcr.io/cross-rs/aarch64-linux-android:main' --tag ghcr.io/cross-rs/aarch64-linux-android:local --label 'org.cross-rs.for-cross-target=aarch64-linux-android' --label 'org.cross-rs.runs-with=x86_64-unknown-linux-gnu' -f /home/ahuszagh/git/cross/docker/Dockerfile.aarch64-linux-android --progress auto .` failed with exit status: 125

Location:
   /rustc/a8314ef7d0ec7b75c336af2c9857bfaf43002bfc/library/core/src/convert/mod.rs:55

What target(s) are you cross-compiling for?

aarch64-linux-android

Which operating system is the host (e.g computer cross is on) running?

• macOS
• Windows
• Linux / BSD
• other OS (specify in description)

What architecture is the host?

• x86_64 / AMD64
• arm32
• arm64 (including Mac M1)

What container engine is cross using?

• docker
• podman
• other container engine (specify in description)

cross version

cross 0.2.4 (d92e563)

Additional information / notes

Removing the --cache-from step fixes the issue. We should probably also add a build image step for podman, using the fast image build (x86_64-unknown-linux-gnu) to avoid this issue in the future. The podman version is 4.2.0.

[Alexhuszagh]

It seems --cache-from only supports a repository using podman, and this might be true for other container engines. type=registry might be implicit. type=registry is the default for docker, so we should be able to omit it.

[Emilgardis]

I don't think there is a situation where not being explicit about it is bad. Removing the explicitness sounds good 👍🏼