Build on Debian fails with "doc alias attribute expects a string:"

[sylvestre]

Trying to package selinux for Debian, I am getting:

     Running `CARGO=/usr/bin/cargo CARGO_CRATE_NAME=selinux CARGO_MANIFEST_DIR=/<<PKGBUILDDIR>> CARGO_PKG_AUTHORS='Koutheir Attouchi <koutheir@gmail.com>' CARGO_PKG_DESCRIPTION='Flexible Mandatory Access Control for Linux' CARGO_PKG_HOMEPAGE='' CARGO_PKG_LICENSE=MIT CARGO_PKG_LICENSE_FILE='' CARGO_PKG_NAME=selinux CARGO_PKG_REPOSITORY='https://github.com/koutheir/selinux' CARGO_PKG_VERSION=0.2.2 CARGO_PKG_VERSION_MAJOR=0 CARGO_PKG_VERSION_MINOR=2 CARGO_PKG_VERSION_PATCH=2 CARGO_PKG_VERSION_PRE='' LD_LIBRARY_PATH='/<<PKGBUILDDIR>>/target/debug/deps:/usr/lib' rustc --crate-name selinux --edition=2018 src/lib.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type lib --emit=dep-info,metadata,link -Cembed-bitcode=no -C debuginfo=2 -C metadata=82c54164d593785f -C extra-filename=-82c54164d593785f --out-dir /<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps --target x86_64-unknown-linux-gnu -C incremental=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/incremental -L dependency=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps -L dependency=/<<PKGBUILDDIR>>/target/debug/deps --extern bitflags=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/libbitflags-3f47185136d2e6bc.rmeta --extern libc=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/liblibc-c7d93ddab2220a9b.rmeta --extern once_cell=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/libonce_cell-453a2446d2f99dbf.rmeta --extern reference_counted_singleton=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/libreference_counted_singleton-3f025b9280c502cf.rmeta --extern selinux_sys=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/libselinux_sys-d5eb7bdc26ae0b3d.rmeta --extern thiserror=/<<PKGBUILDDIR>>/target/x86_64-unknown-linux-gnu/debug/deps/libthiserror-3632fe4357e3cad5.rmeta -C debuginfo=2 --cap-lints warn -C linker=x86_64-linux-gnu-gcc -C link-arg=-Wl,-z,relro --remap-path-prefix /<<PKGBUILDDIR>>=/usr/share/cargo/registry/selinux-0.2.2 -L native=/usr/lib/x86_64-linux-gnu`

error: doc alias attribute expects a string: #[doc(alias = "0")]
    --> src/lib.rs:1846:7
     |
1846 | #[doc(alias("is_selinux_enabled", "is_selinux_mls_enabled"))]
     |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

[koutheir]

Can you please provide the version of the rust tool chain you're using?

[sylvestre]

With rustc 1.48

[sylvestre]

the one is Debian stable, testing and unstable (experimental is 1.52)

[koutheir]

Specifying multiple aliases became possible after 1.48 was released. To avoid this trivial issue, I'll replace the affected doc(alias) directives with multiple directives specifying one alias at a time.

See: rust-lang/rust#82846

[koutheir]

This fix is integrated into version 0.2.3.

[sylvestre]

Sorry but it has to be done on all the files, not only for this one :/
Here is the super ugly patch that I need to write to be able to build:
https://salsa.debian.org/rust-team/debcargo-conf/-/blob/master/src/selinux/debian/patches/disable-check-doc.diff

[koutheir]

Why did you remove the aliases with that patch? That's not what the error complains about.

[sylvestre]

Because it was easier to do that quickly: the package needs to go in review in Debian and it can take months. So, I was confident a fix would be there before it gets accepted in Debian

[koutheir]

So the reason is procedure, fine. Still, version 0.2.3 fixes this issue correctly without removing the aliases entirely.