bindgen spells the log callback's va_list parameter the way the host
that ran it does. The bindings are generated once and compiled
everywhere, so that spelling only happens to be right on the generating
host.
This was alright for most hosts but is fragile on aarch64 where va_list
is a plain 32 bytes struct.
Given we only forward the list to vsnprintf, extracting and simplifying
the cross-platform rust implementation from the unstable std-lib is
cheap and sound. We will just have to re-export the official type once
it's stablilized.
Force-pushing a branch several times in a row leaves the older pipelines
running to completion against commits nobody is waiting on. Mark the job
interruptible so GitLab can reclaims the runners.
cargo 1.82 has no MSRV-aware resolution, so a dependency publishing a
release that needs a newer toolchain would break the build on a change
that touched nothing. Pinning the resolution makes builds reproducible.
Consumers ignore the lock file of a dependency, so this constrains
nothing downstream. Committing it for libraries is the current cargo
recommendation.
bindgen's output is a committed source file, so the version producing it
has to be pinned like any other input. With `bindgen = "0.72"` floating,
a patch release that changes formatting silently changes the generated
bindings.
`--locked` on the alias keeps cargo from quietly updating it when the
manifest disagrees.
Generating the FFI bindings at consumer build time is unecessary. The
`use-bindgen` Cargo feature was non-additive, and forced bindgen +
libclang onto every build that opted in, for a decision that is really
about the maintainer's environment, not the public API.
Move binding generation out of the build entirely, following the xtask
pattern[^1]:
- build.rs is reduced to locating and linking libvlc.
- Regeneration lives in a `xtask` crate, run with `cargo xtask bindgen`.
[^1]: <https://github.com/matklad/cargo-xtask>
pkg-config was probed up to three times per build: once inside
generate_bindings for the header include paths, once for linking, and
then main unconditionally emitted `cargo:rustc-link-lib=vlc` on top of the
directives the successful probe already prints, libvlc ended up on
the link line two or three times.
Probe a single time in main and thread the resulting Library into
generate_bindings for its include paths. Drop the manual rustc-link-lib
line, since a successful pkg_config probe emits it.
binding.rs generation with bindgen is optional.
By default, a pre-generated binding.rs is copied in OUT_DIR. This allows
for example to build on Windows and link against a standard VLC
installation.
Feature "use-bindgen" will trigger binding generation.
Alaric Senat