rust: bindgen: upgrade to 0.65.1
authorAakash Sen Sharma <aakashsensharma@gmail.com>
Mon, 12 Jun 2023 19:43:11 +0000 (01:13 +0530)
committerMiguel Ojeda <ojeda@kernel.org>
Mon, 14 Aug 2023 22:37:22 +0000 (00:37 +0200)
commit08ab786556ff177086ce93b26daf2a58edd10968
treecb4c0005d3b762e70f8542f08fb9ee046a76db80
parent9418e686047421dcd416f694ea72fb9edeef3688
rust: bindgen: upgrade to 0.65.1

In LLVM 16, anonymous items may return names like `(unnamed union at ..)`
rather than empty names [1], which breaks Rust-enabled builds because
bindgen assumed an empty name instead of detecting them via
`clang_Cursor_isAnonymous` [2]:

    $ make rustdoc LLVM=1 CLIPPY=1 -j$(nproc)
      RUSTC L rust/core.o
      BINDGEN rust/bindings/bindings_generated.rs
      BINDGEN rust/bindings/bindings_helpers_generated.rs
      BINDGEN rust/uapi/uapi_generated.rs
    thread 'main' panicked at '"ftrace_branch_data_union_(anonymous_at__/_/include/linux/compiler_types_h_146_2)" is not a valid Ident', .../proc-macro2-1.0.24/src/fallback.rs:693:9
    ...
    thread 'main' panicked at '"ftrace_branch_data_union_(anonymous_at__/_/include/linux/compiler_types_h_146_2)" is not a valid Ident', .../proc-macro2-1.0.24/src/fallback.rs:693:9
    ...

This was fixed in bindgen 0.62.0. Therefore, upgrade bindgen to
a more recent version, 0.65.1, to support LLVM 16.

Since bindgen 0.58.0 changed the `--{white,black}list-*` flags to
`--{allow,block}list-*` [3], update them on our side too.

In addition, bindgen 0.61.0 moved its CLI utility into a binary crate
called `bindgen-cli` [4]. Thus update the installation command in the
Quick Start guide.

Moreover, bindgen 0.61.0 changed the default functionality to bind
`size_t` to `usize` [5] and added the `--no-size_t-is-usize` flag
to not bind `size_t` as `usize`. Then bindgen 0.65.0 removed
the `--size_t-is-usize` flag [6]. Thus stop passing the flag to bindgen.

Finally, bindgen 0.61.0 added support for the `noreturn` attribute (in
its different forms) [7]. Thus remove the infinite loop in our Rust
panic handler after calling `BUG()`, since bindgen now correctly
generates a `BUG()` binding that returns `!` instead of `()`.

Link: https://github.com/llvm/llvm-project/commit/19e984ef8f49bc3ccced15621989fa9703b2cd5b
Link: https://github.com/rust-lang/rust-bindgen/pull/2319
Link: https://github.com/rust-lang/rust-bindgen/pull/1990
Link: https://github.com/rust-lang/rust-bindgen/pull/2284
Link: https://github.com/rust-lang/rust-bindgen/commit/cc78b6fdb6e829e5fb8fa1639f2182cb49333569
Link: https://github.com/rust-lang/rust-bindgen/pull/2408
Link: https://github.com/rust-lang/rust-bindgen/issues/2094
Signed-off-by: Aakash Sen Sharma <aakashsensharma@gmail.com>
Closes: https://github.com/Rust-for-Linux/linux/issues/1013
Tested-by: Ariel Miculas <amiculas@cisco.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20230612194311.24826-1-aakashsensharma@gmail.com
[ Reworded commit message. Mentioned the `bindgen-cli` binary crate
  change, linked to it and updated the Quick Start guide. Re-added a
  deleted "as" word in a code comment and reflowed comment to respect
  the maximum length. ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Documentation/process/changes.rst
Documentation/rust/quick-start.rst
rust/Makefile
rust/helpers.c
rust/kernel/lib.rs
scripts/min-tool-version.sh