🎱
On Fri, 30 Aug 2024, 04:19 Junjie Mao, <junjie....@intel.com> wrote:
> On 8/28/2024 9:08 PM, Alex Bennée wrote:
> > Manos Pitsidianakis <manos.pitsidiana...@linaro.org> writes:
> >
> >> Add rust/qemu-api, which exposes rust-bindgen generated FFI bindings and
> >> provides some declaration macros for symbols visible to the rest of
> >> QEMU.
> >
> > As mentioned on IRC I'm hitting a compilation error that bisects to this
> > commit:
> >
> > [148/1010] Generating bindings for Rust rustmod-bindgen-rust_wrapper.h
> > FAILED: bindings.rs
> > /home/alex/.cargo/bin/bindgen ../../rust/wrapper.h --output
> /home/alex/lsrc/qemu.git/builds/rust/bindings.rs --disable-header-comment
> --raw-line '// @generated' --ctypes-prefix core::ffi --formatter rustfmt
> --generate-block --generate-cstr --impl-debug --merge-extern-blocks
> --no-doc-comments --use-core --with-derive-default --allowlist-file
> '/home/alex/lsrc/qemu.git/include/.*' --allowlist-file
> '/home/alex/lsrc/qemu.git/.*' --allowlist-file
> '/home/alex/lsrc/qemu.git/builds/rust/.*' -- -I/home/alex/lsrc/qemu.git/.
> -I/home/alex/lsrc/qemu.git/builds/rust/. -I/home/alex/lsrc/qemu.git/include
> -I/home/alex/lsrc/qemu.git/builds/rust/include -I/usr/include/capstone
> -I/usr/include/p11-kit-1 -I/usr/include/pixman-1 -I/usr/include/libpng16
> -I/usr/include/spice-server -I/usr/include/spice-1 -I/usr/include/spice-1
> -DSTRUCT_IOVEC_DEFINED -I/usr/include/libusb-1.0 -I/usr/include/SDL2
> -D_REENTRANT -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -pthread
> -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/gio-unix-2.0
> -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
> -pthread -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/slirp
> -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
> -DNCURSES_WIDECHAR=1 -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600
> -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
> -I/usr/include/gtk-3.0 -I/usr/include/pango-1.0 -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/harfbuzz
> -I/usr/include/freetype2 -I/usr/include/libpng16 -I/usr/include/libmount
> -I/usr/include/blkid -I/usr/include/fribidi -I/usr/include/cairo
> -I/usr/include/pixman-1 -I/usr/include/gdk-pixbuf-2.0
> -I/usr/include/x86_64-linux-gnu -I/usr/include/gio-unix-2.0
> -I/usr/include/atk-1.0 -I/usr/include/at-spi2-atk/2.0
> -I/usr/include/at-spi-2.0 -I/usr/include/dbus-1.0
> -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -pthread
> -I/usr/include/gtk-3.0 -I/usr/include/pango-1.0 -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/harfbuzz
> -I/usr/include/freetype2 -I/usr/include/libpng16 -I/usr/include/libmount
> -I/usr/include/blkid -I/usr/include/fribidi -I/usr/include/cairo
> -I/usr/include/pixman-1 -I/usr/include/gdk-pixbuf-2.0
> -I/usr/include/x86_64-linux-gnu -I/usr/include/gio-unix-2.0
> -I/usr/include/atk-1.0 -I/usr/include/at-spi2-atk/2.0
> -I/usr/include/at-spi-2.0 -I/usr/include/dbus-1.0
> -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -pthread
> -I/usr/include/vte-2.91 -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/libmount
> -I/usr/include/blkid -I/usr/include/pango-1.0 -I/usr/include/harfbuzz
> -I/usr/include/freetype2 -I/usr/include/libpng16 -I/usr/include/fribidi
> -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/gtk-3.0
> -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/x86_64-linux-gnu
> -I/usr/include/gio-unix-2.0 -I/usr/include/atk-1.0
> -I/usr/include/at-spi2-atk/2.0 -I/usr/include/at-spi-2.0
> -I/usr/include/dbus-1.0 -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include
> -pthread -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/spice-server
> -I/usr/include/spice-1 -I/usr/include/cacard -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/nss
> -I/usr/include/nspr -I/usr/include/PCSC -pthread -D_REENTRANT
> -I/usr/include/pipewire-0.3 -I/usr/include/spa-0.2 -D_REENTRANT
> -I/usr/include/p11-kit-1 -I/usr/include/fuse3
> -I/usr/include/x86_64-linux-gnu -D_FILE_OFFSET_BITS=64
> -D__USE_FILE_OFFSET64 -D__USE_LARGEFILE64 -DUSE_POSIX_ACLS=1
> -I/usr/include/uuid -I/usr/include/glib-2.0
> -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -I/usr/include/p11-kit-1
> -I/usr/include/p11-kit-1 -I/usr/include/p11-kit-1 -I/usr/include/p11-kit-1
> -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE
> -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include
> -std=gnu11 -MD -MQ ../../rust/wrapper.h -MF wrapper.h.d
> > /usr/include/liburing.h:296:3: error: use of undeclared identifier
> 'memory_order_release'
> > /usr/include/liburing.h:1080:11: error: use of undeclared identifier
> 'memory_order_acquire'
> > /usr/include/liburing.h:1116:9: error: use of undeclared identifier
> 'memory_order_acquire'
> > /usr/include/liburing.h:1125:9: error: use of undeclared identifier
> 'memory_order_relaxed'
> > /usr/include/liburing.h:1161:2: error: use of undeclared identifier
> 'memory_order_relaxed'
> > /usr/include/liburing.h:1197:19: error: use of undeclared identifier
> 'memory_order_acquire'
> > /usr/include/liburing.h:1267:10: error: use of undeclared identifier
> 'memory_order_relaxed'
> > /usr/include/liburing.h:1269:10: error: use of undeclared identifier
> 'memory_order_acquire'
> > /usr/include/liburing.h:1320:2: error: use of undeclared identifier
> 'memory_order_release'
> > panicked at
> /home/alex/.cargo/registry/src/index.crates.io-6f17d22bba15001f/bindgen-cli-0.69.4/main.rs:52
> :36:
> > Unable to generate bindings:
> ClangDiagnostic("/usr/include/liburing.h:296:3: error: use of undeclared
> identifier 'memory_order_release'\n/usr/include/liburing.h:1080:11: error:
> use of undeclared identifier
> 'memory_order_acquire'\n/usr/include/liburing.h:1116:9: error: use of
> undeclared identifier
> 'memory_order_acquire'\n/usr/include/liburing.h:1125:9: error: use of
> undeclared identifier
> 'memory_order_relaxed'\n/usr/include/liburing.h:1161:2: error: use of
> undeclared identifier
> 'memory_order_relaxed'\n/usr/include/liburing.h:1197:19: error: use of
> undeclared identifier
> 'memory_order_acquire'\n/usr/include/liburing.h:1267:10: error: use of
> undeclared identifier
> 'memory_order_relaxed'\n/usr/include/liburing.h:1269:10: error: use of
> undeclared identifier
> 'memory_order_acquire'\n/usr/include/liburing.h:1320:2: error: use of
> undeclared identifier 'memory_order_release'\n")
>
> Those missing identifiers should have been defined in stdatomic.h which is
> part
> of C11. You can check if that header exists under the default header
> search
> paths (which is listed by clang -E -Wp,-v -) and whether that file
> declares
> those enum constants. If so, you can further check whether there is any
> stdatomic.h elsewhere that shadows the standard one.
>
Indeed. These are in the compiler's own header files. I had problems on
Debian when using clang-14 and clang-15 but I got rid of them after I
upgraded to newer versions. If anyone can confirm/reproduce this we can add
a meson warning check?
>
> > And I wasn't able to force the newer clang with:
> >
> > env CLANG_PATH=/usr/bin/clang-15 ../../configure '--disable-docs'
> --target-list=aarch64-softmmu --enable-rust
> >
> > So if clang is required for bindgen we at least need:
> >
> > - to probe for clang (separately from --cc)
> > - allow the user to override the default
> > - pass the clang we want to use somehow to bindgen
> >
> > Briefly looking at the bindgen code I see:
> >
> > fn main() {
> > let out_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
> >
> > let mut dst =
> >
> File::create(Path::new(&out_dir).join("host-target.txt")).unwrap();
> > dst.write_all(env::var("TARGET").unwrap().as_bytes())
> > .unwrap();
> >
> > // On behalf of clang_sys, rebuild ourselves if important
> configuration
> > // variables change, to ensure that bindings get rebuilt if the
> > // underlying libclang changes.
> > println!("cargo:rerun-if-env-changed=LLVM_CONFIG_PATH");
> > println!("cargo:rerun-if-env-changed=LIBCLANG_PATH");
> > println!("cargo:rerun-if-env-changed=LIBCLANG_STATIC_PATH");
> > println!("cargo:rerun-if-env-changed=BINDGEN_EXTRA_CLANG_ARGS");
> > println!(
> > "cargo:rerun-if-env-changed=BINDGEN_EXTRA_CLANG_ARGS_{}",
> > std::env::var("TARGET").unwrap()
> > );
> > println!(
> > "cargo:rerun-if-env-changed=BINDGEN_EXTRA_CLANG_ARGS_{}",
> > std::env::var("TARGET").unwrap().replace('-', "_")
> > );
> > }
>
> This is build.rs which is a build script invoked by cargo. The entry of
> the
> bindgen executable is in the bindgen-cli crate.
>
> ---
> Best Regards
> Junjie Mao
>
> >
> > So I wonder if this depends on what libclang versions can be found when
> > cargo builds it? Although if it does it must do so dynamically:
> >
> > $ ldd /home/alex/.cargo/bin/bindgen
> > linux-vdso.so.1 (0x00007f7cb43d8000)
> > libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1
> (0x00007f7cb438c000)
> > libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6
> (0x00007f7cb42ad000)
> > libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6
> (0x00007f7cb3a1f000)
> > /lib64/ld-linux-x86-64.so.2 (0x00007f7cb43da000)
> >
>
