Automatically generate BDWGC bindings

.buildbot.config.toml

@@ -1,5 +1,6 @@
 [alloy]
 bdwgc-assertions = true
+bdwgc-link-shared = true
 
 [rust]
 codegen-units = 0           # Use many compilation units.

.buildbot.sh

@@ -28,7 +28,7 @@ sh rustup.sh --default-host x86_64-unknown-linux-gnu \
 	-y
 export PATH=$(pwd)/.cargo/bin/:$PATH
 
-rustup toolchain link alloy build/x86_64-unknown-linux-gnu/stage1
+rustup toolchain link alloy build/x86_64-unknown-linux-gnu/stage2
 
 # Build and test yksom
 git clone --recursive https://github.com/softdevteam/yksom

.buildbot_dockerfile_debian

@@ -2,7 +2,8 @@ FROM debian:latest
 ARG CI_UID
 RUN useradd -m -u ${CI_UID} ci
 RUN apt-get update && \
-    apt-get -y install build-essential curl cmake python3 git ninja-build time autoconf libtool libssl-dev pkg-config
+    apt-get -y install build-essential curl cmake python3 git ninja-build \
+    time autoconf libclang-dev libtool libssl-dev pkg-config
 WORKDIR /ci
 RUN chown ${CI_UID}:${CI_UID} .
 COPY --chown=${CI_UID}:${CI_UID} . .

.gitmodules

@@ -54,3 +54,6 @@
 [submodule "src/bdwgc"]
 	path = src/bdwgc
 	url = https://github.com/softdevteam/bdwgc
+[submodule "src/tools/bindgen"]
+	path = src/tools/bindgen
+	url = https://github.com/rust-lang/rust-bindgen.git

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -1318,6 +1318,12 @@ fn link_sanitizer_runtime(
     }
 }
 
+fn add_bdwgc(sess: &Session, linker: &mut dyn Linker) {
+    let sysroot = sess.sysroot.clone();
+    linker.link_args(&["-rpath", &sysroot.join("lib").to_str().unwrap()]);
+    linker.link_dylib_by_name("gc", false, false);
+}
+
 /// Returns a boolean indicating whether the specified crate should be ignored
 /// during LTO.
 ///
@@ -2254,6 +2260,8 @@ fn linker_with_args(
     // Sanitizer libraries.
     add_sanitizer_libraries(sess, flavor, crate_type, cmd);
 
+    add_bdwgc(sess, cmd);
+
     // Object code from the current crate.
     // Take careful note of the ordering of the arguments we pass to the linker
     // here. Linkers will assume that things on the left depend on things to the

library/Cargo.lock

@@ -409,6 +409,7 @@ dependencies = [
 name = "sysroot"
 version = "0.0.0"
 dependencies = [
+ "bdwgc",
  "proc_macro",
  "profiler_builtins",
  "std",

library/bdwgc/build.rs

@@ -1,53 +1,39 @@
+use std::env;
+use std::path::Path;
+use std::process::Command;
 #[cfg(not(all(target_pointer_width = "64", target_arch = "x86_64")))]
 compile_error!("Requires x86_64 with 64 bit pointer width.");
 
-#[cfg(not(feature = "link-shared"))]
-fn build_bdwgc() {
-    use std::env;
-    use std::path::PathBuf;
-    use std::process::Command;
-
-    const BDWGC_REPO: &str = "../../src/bdwgc";
-    const BDWGC_BUILD_DIR: &str = "lib";
-
-    let out_dir = env::var("OUT_DIR").unwrap();
-    let bdwgc_src = PathBuf::from(BDWGC_REPO);
-
-    if bdwgc_src.read_dir().unwrap().count() == 0 {
-        Command::new("git")
-            .args(["submodule", "update", "--init", BDWGC_REPO])
-            .output()
-            .expect("Failed to clone BDWGC repo");
-    }
-
-    let mut build_dir = PathBuf::from(&out_dir);
-    build_dir.push(BDWGC_BUILD_DIR);
-
-    let mut build = cmake::Config::new(&bdwgc_src);
-    build
-        .pic(true)
-        .define("BUILD_SHARED_LIBS", "OFF")
-        .define("enable_parallel_mark", "Off")
-        .cflag("-DGC_ALWAYS_MULTITHREADED");
-
-    #[cfg(feature = "gc-assertions")]
-    build.define("enable_gc_assertions", "ON");
-
-    #[cfg(not(feature = "gc-debug"))]
-    build.profile("Release");
-
-    #[cfg(feature = "gc-debug")]
-    build.profile("Debug");
-
-    build.build();
-
-    println!("cargo:rustc-link-search=native={}", &build_dir.display());
-    println!("cargo:rustc-link-lib=static=gc");
-}
-
 fn main() {
-    #[cfg(not(feature = "link-shared"))]
-    build_bdwgc();
-    #[cfg(feature = "link-shared")]
-    println!("cargo:rustc-link-lib=dylib=gc");
+    let cwd = env::var("CARGO_MANIFEST_DIR").unwrap();
+    let header = Path::new(&cwd)
+        .parent()
+        .unwrap()
+        .parent()
+        .unwrap()
+        .join("src")
+        .join("bdwgc")
+        .join("include")
+        .join("gc.h");
+
+    let bindgen = std::env::var("RUSTC_BINDGEN").unwrap();
+    let out = Path::new(&env::var("OUT_DIR").unwrap()).join("bindings.rs");
+    let status = Command::new(bindgen)
+        .args(&[
+            "--ctypes-prefix",
+            "libc",
+            "--use-core",
+            "-o",
+            out.to_str().unwrap(),
+            header.to_str().unwrap(),
+            "--",
+            "-DGC_THREADS",
+        ])
+        .status()
+        .unwrap();
+
+    if !status.success() {
+        panic!("bindgen failed with status: {:?}", status);
+    }
+    println!("cargo::rustc-link-lib=dylib=gc");
 }

library/bdwgc/src/lib.rs

@@ -1,4 +1,8 @@
 #![no_std]
+#![allow(non_camel_case_types)]
+#![allow(non_upper_case_globals)]
+
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
 
 #[repr(C)]
 #[derive(Default)]
@@ -29,69 +33,3 @@ pub struct ProfileStats {
     /// Number of bytes freed explicitly since the recent GC.
     pub expl_freed_bytes_since_gc: usize,
 }
-
-#[link(name = "gc")]
-extern "C" {
-    pub fn GC_malloc(nbytes: usize) -> *mut u8;
-
-    pub fn GC_posix_memalign(mem_ptr: *mut *mut u8, align: usize, nbytes: usize) -> i32;
-
-    pub fn GC_realloc(old: *mut u8, new_size: usize) -> *mut u8;
-
-    pub fn GC_free(dead: *mut u8);
-
-    pub fn GC_base(mem_ptr: *mut u8) -> *mut u8;
-
-    pub fn GC_register_finalizer(
-        ptr: *mut u8,
-        finalizer: Option<unsafe extern "C" fn(*mut u8, *mut u8)>,
-        client_data: *mut u8,
-        old_finalizer: *mut extern "C" fn(*mut u8, *mut u8),
-        old_client_data: *mut *mut u8,
-    );
-
-    pub fn GC_register_finalizer_no_order(
-        ptr: *mut u8,
-        finalizer: Option<unsafe extern "C" fn(*mut u8, *mut u8)>,
-        client_data: *mut u8,
-        old_finalizer: *mut extern "C" fn(*mut u8, *mut u8),
-        old_client_data: *mut *mut u8,
-    );
-
-    pub fn GC_gcollect();
-
-    pub fn GC_thread_is_registered() -> u32;
-
-    pub fn GC_pthread_create(
-        native: *mut libc::pthread_t,
-        attr: *const libc::pthread_attr_t,
-        f: extern "C" fn(_: *mut libc::c_void) -> *mut libc::c_void,
-        value: *mut libc::c_void,
-    ) -> libc::c_int;
-
-    pub fn GC_pthread_join(native: libc::pthread_t, value: *mut *mut libc::c_void) -> libc::c_int;
-
-    pub fn GC_pthread_exit(value: *mut libc::c_void) -> !;
-
-    pub fn GC_pthread_detach(thread: libc::pthread_t) -> libc::c_int;
-
-    pub fn GC_init();
-
-    pub fn GC_keep_alive(ptr: *mut u8);
-
-    pub fn GC_set_finalize_on_demand(state: i32);
-
-    pub fn GC_set_finalizer_notifier(f: extern "C" fn());
-
-    pub fn GC_should_invoke_finalizers() -> u32;
-
-    pub fn GC_invoke_finalizers() -> u64;
-
-    pub fn GC_get_gc_no() -> u64;
-
-    pub fn GC_enable();
-
-    pub fn GC_is_disabled() -> i32;
-
-    pub fn GC_disable();
-}

library/std/src/gc.rs

@@ -125,7 +125,7 @@ unsafe fn gc_malloc(layout: Layout) -> *mut u8 {
 #[inline]
 unsafe fn gc_realloc(ptr: *mut u8, old_layout: Layout, new_size: usize) -> *mut u8 {
     if old_layout.align() <= MIN_ALIGN && old_layout.align() <= new_size {
-        unsafe { bdwgc::GC_realloc(ptr, new_size) as *mut u8 }
+        unsafe { bdwgc::GC_realloc(ptr as *mut libc::c_void, new_size) as *mut u8 }
     } else {
         unsafe {
             let new_layout = Layout::from_size_align_unchecked(new_size, old_layout.align());
@@ -144,7 +144,7 @@ unsafe fn gc_realloc(ptr: *mut u8, old_layout: Layout, new_size: usize) -> *mut
 #[inline]
 unsafe fn gc_free(ptr: *mut u8, _: Layout) {
     unsafe {
-        bdwgc::GC_free(ptr);
+        bdwgc::GC_free(ptr as *mut libc::c_void);
     }
 }
 
@@ -209,7 +209,7 @@ pub fn init() {
     unsafe {
         bdwgc::GC_init();
         bdwgc::GC_set_finalize_on_demand(1);
-        bdwgc::GC_set_finalizer_notifier(notify_finalizer_thread);
+        bdwgc::GC_set_finalizer_notifier(Some(notify_finalizer_thread));
         #[cfg(feature = "bdwgc-disable")]
         bdwgc::GC_disable()
     }
@@ -220,7 +220,7 @@ pub fn thread_registered() -> bool {
 }
 
 pub fn keep_alive<T>(ptr: *mut T) {
-    unsafe { bdwgc::GC_keep_alive(ptr as *mut u8) }
+    unsafe { bdwgc::GC_keep_alive(ptr as *mut _ as u64) }
 }
 
 pub fn is_enabled() -> bool {
@@ -606,7 +606,7 @@ impl<T> Gc<T> {
             }
         }
 
-        unsafe extern "C" fn finalizer_shim<T>(obj: *mut u8, _: *mut u8) {
+        unsafe extern "C" fn finalizer_shim<T>(obj: *mut libc::c_void, _: *mut libc::c_void) {
             let drop_fn = drop_in_place::<GcBox<T>>;
             unsafe { drop_fn(obj as *mut GcBox<T>) };
         }
@@ -625,7 +625,7 @@ impl<T> Gc<T> {
         let ptr = Box::leak(Box::new_in(GcBox { value }, GcAllocator));
         unsafe {
             bdwgc::GC_register_finalizer_no_order(
-                ptr as *mut _ as *mut u8,
+                ptr as *mut _ as *mut libc::c_void,
                 Some(finalizer_shim::<T>),
                 ptr::null_mut(),
                 ptr::null_mut(),

library/std/src/sys/pal/unix/thread.rs

@@ -85,8 +85,12 @@ impl Thread {
             };
         }
 
-        let ret =
-            crate::bdwgc::GC_pthread_create(&mut native, attr.as_ptr(), thread_start, p as *mut _);
+        let ret = crate::bdwgc::GC_pthread_create(
+            &mut native,
+            attr.as_ptr() as *const bdwgc::pthread_attr_t,
+            Some(thread_start),
+            p as *mut _,
+        );
         // Note: if the thread creation fails and this assert fails, then p will
         // be leaked. However, an alternative design could cause double-free
         // which is clearly worse.

library/sysroot/Cargo.toml

@@ -11,6 +11,7 @@ proc_macro = { path = "../proc_macro", public = true }
 profiler_builtins = { path = "../profiler_builtins", optional = true }
 std = { path = "../std", public = true }
 test = { path = "../test", public = true }
+bdwgc = { path = "../bdwgc", public = true }
 
 # Forward features to the `std` crate as necessary
 [features]

rustfmt.toml

@@ -38,6 +38,7 @@ ignore = [
     "src/doc/rust-by-example",
     "src/doc/rustc-dev-guide",
     "src/llvm-project",
+    "src/tools/bindgen",
     "src/tools/cargo",
     "src/tools/clippy",
     "src/tools/enzyme",