From 08ab786556ff177086ce93b26daf2a58edd10968 Mon Sep 17 00:00:00 2001
From: Aakash Sen Sharma <aakashsensharma@gmail.com>
Date: Tue, 13 Jun 2023 01:13:11 +0530
Subject: [PATCH] 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 [1]
Link: https://github.com/rust-lang/rust-bindgen/pull/2319 [2]
Link: https://github.com/rust-lang/rust-bindgen/pull/1990 [3]
Link: https://github.com/rust-lang/rust-bindgen/pull/2284 [4]
Link: https://github.com/rust-lang/rust-bindgen/commit/cc78b6fdb6e829e5fb8fa1639f2182cb49333569 [5]
Link: https://github.com/rust-lang/rust-bindgen/pull/2408 [6]
Link: https://github.com/rust-lang/rust-bindgen/issues/2094 [7]
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 | 2 +-
Documentation/rust/quick-start.rst | 2 +-
rust/Makefile | 6 +++---
rust/helpers.c | 15 +++++++--------
rust/kernel/lib.rs | 3 ---
scripts/min-tool-version.sh | 2 +-
6 files changed, 13 insertions(+), 17 deletions(-)
diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 1382bccc88188..0bbd040f6a55b 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -32,7 +32,7 @@ you probably needn't concern yourself with pcmciautils.
GNU C 5.1 gcc --version
Clang/LLVM (optional) 11.0.0 clang --version
Rust (optional) 1.71.1 rustc --version
-bindgen (optional) 0.56.0 bindgen --version
+bindgen (optional) 0.65.1 bindgen --version
GNU make 3.82 make --version
bash 4.2 bash --version
binutils 2.25 ld -v
diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 58a183bb90b1e..2cdf75eeae1d8 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -98,7 +98,7 @@ the ``bindgen`` tool. A particular version is required.
Install it via (note that this will download and build the tool from source)::
- cargo install --locked --version $(scripts/min-tool-version.sh bindgen) bindgen
+ cargo install --locked --version $(scripts/min-tool-version.sh bindgen) bindgen-cli
``bindgen`` needs to find a suitable ``libclang`` in order to work. If it is
not found (or a different ``libclang`` than the one found should be used),
diff --git a/rust/Makefile b/rust/Makefile
index b278908c19e58..c3dfb3f6071bf 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -300,7 +300,7 @@ quiet_cmd_bindgen = BINDGEN $@
$(BINDGEN) $< $(bindgen_target_flags) \
--use-core --with-derive-default --ctypes-prefix core::ffi --no-layout-tests \
--no-debug '.*' \
- --size_t-is-usize -o $@ -- $(bindgen_c_flags_final) -DMODULE \
+ -o $@ -- $(bindgen_c_flags_final) -DMODULE \
$(bindgen_target_cflags) $(bindgen_target_extra)
$(obj)/bindings/bindings_generated.rs: private bindgen_target_flags = \
@@ -320,8 +320,8 @@ $(obj)/uapi/uapi_generated.rs: $(src)/uapi/uapi_helper.h \
# given it is `libclang`; but for consistency, future Clang changes and/or
# a potential future GCC backend for `bindgen`, we disable it too.
$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_flags = \
- --blacklist-type '.*' --whitelist-var '' \
- --whitelist-function 'rust_helper_.*'
+ --blocklist-type '.*' --allowlist-var '' \
+ --allowlist-function 'rust_helper_.*'
$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_cflags = \
-I$(objtree)/$(obj) -Wno-missing-prototypes -Wno-missing-declarations
$(obj)/bindings/bindings_helpers_generated.rs: private bindgen_target_extra = ; \
diff --git a/rust/helpers.c b/rust/helpers.c
index f946f2ea640a3..ebd69490127b4 100644
--- a/rust/helpers.c
+++ b/rust/helpers.c
@@ -138,19 +138,18 @@ void rust_helper_put_task_struct(struct task_struct *t)
EXPORT_SYMBOL_GPL(rust_helper_put_task_struct);
/*
- * We use `bindgen`'s `--size_t-is-usize` option to bind the C `size_t` type
- * as the Rust `usize` type, so we can use it in contexts where Rust
- * expects a `usize` like slice (array) indices. `usize` is defined to be
- * the same as C's `uintptr_t` type (can hold any pointer) but not
- * necessarily the same as `size_t` (can hold the size of any single
- * object). Most modern platforms use the same concrete integer type for
+ * `bindgen` binds the C `size_t` type as the Rust `usize` type, so we can
+ * use it in contexts where Rust expects a `usize` like slice (array) indices.
+ * `usize` is defined to be the same as C's `uintptr_t` type (can hold any
+ * pointer) but not necessarily the same as `size_t` (can hold the size of any
+ * single object). Most modern platforms use the same concrete integer type for
* both of them, but in case we find ourselves on a platform where
* that's not true, fail early instead of risking ABI or
* integer-overflow issues.
*
* If your platform fails this assertion, it means that you are in
- * danger of integer-overflow bugs (even if you attempt to remove
- * `--size_t-is-usize`). It may be easiest to change the kernel ABI on
+ * danger of integer-overflow bugs (even if you attempt to add
+ * `--no-size_t-is-usize`). It may be easiest to change the kernel ABI on
* your platform such that `size_t` matches `uintptr_t` (i.e., to increase
* `size_t`, because `uintptr_t` has to be at least as big as `size_t`).
*/
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 85b2612099775..d59041ff5ff21 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -93,7 +93,4 @@ fn panic(info: &core::panic::PanicInfo<'_>) -> ! {
pr_emerg!("{}\n", info);
// SAFETY: FFI call.
unsafe { bindings::BUG() };
- // Bindgen currently does not recognize `__noreturn` so `BUG` returns `()`
- // instead of `!`. See <https://github.com/rust-lang/rust-bindgen/issues/2094>.
- loop {}
}
diff --git a/scripts/min-tool-version.sh b/scripts/min-tool-version.sh
index 8da3b53fe36a9..d65ab8bfeaf4b 100755
--- a/scripts/min-tool-version.sh
+++ b/scripts/min-tool-version.sh
@@ -34,7 +34,7 @@ rustc)
echo 1.71.1
;;
bindgen)
- echo 0.56.0
+ echo 0.65.1
;;
*)
echo "$1: unknown tool" >&2
--
2.30.2