Rollup of 6 pull requests

library/core/src/lib.rs

@@ -26,7 +26,8 @@
 //!   assumptions about their semantics: For `memcpy`, `memmove`, `memset`, `memcmp`, and `bcmp`, if
 //!   the `n` parameter is 0, the function is assumed to not be UB. Furthermore, for `memcpy`, if
 //!   source and target pointer are equal, the function is assumed to not be UB.
-//!   (Note that these are [standard assumptions](https://reviews.llvm.org/D86993) among compilers.)
+//!   (Note that these are standard assumptions among compilers:
+//!   [clang](https://reviews.llvm.org/D86993) and [GCC](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=32667) do the same.)
 //!   These functions are often provided by the system libc, but can also be provided by the
 //!   [compiler-builtins crate](https://crates.io/crates/compiler_builtins).
 //!   Note that the library does not guarantee that it will always make these assumptions, so Rust

library/std/src/os/linux/fs.rs

@@ -329,7 +329,14 @@ pub trait MetadataExt {
 impl MetadataExt for Metadata {
     #[allow(deprecated)]
     fn as_raw_stat(&self) -> &raw::stat {
-        unsafe { &*(self.as_inner().as_inner() as *const libc::stat64 as *const raw::stat) }
+        #[cfg(target_env = "musl")]
+        unsafe {
+            &*(self.as_inner().as_inner() as *const libc::stat as *const raw::stat)
+        }
+        #[cfg(not(target_env = "musl"))]
+        unsafe {
+            &*(self.as_inner().as_inner() as *const libc::stat64 as *const raw::stat)
+        }
     }
     fn st_dev(&self) -> u64 {
         self.as_inner().as_inner().st_dev as u64

library/std/src/sys/unix/fd.rs

@@ -126,9 +126,17 @@ impl FileDesc {
     }
 
     pub fn read_at(&self, buf: &mut [u8], offset: u64) -> io::Result<usize> {
-        #[cfg(not(any(target_os = "linux", target_os = "android", target_os = "hurd")))]
+        #[cfg(not(any(
+            all(target_os = "linux", not(target_env = "musl")),
+            target_os = "android",
+            target_os = "hurd"
+        )))]
         use libc::pread as pread64;
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "hurd"))]
+        #[cfg(any(
+            all(target_os = "linux", not(target_env = "musl")),
+            target_os = "android",
+            target_os = "hurd"
+        ))]
         use libc::pread64;
 
         unsafe {
@@ -285,9 +293,17 @@ impl FileDesc {
     }
 
     pub fn write_at(&self, buf: &[u8], offset: u64) -> io::Result<usize> {
-        #[cfg(not(any(target_os = "linux", target_os = "android", target_os = "hurd")))]
+        #[cfg(not(any(
+            all(target_os = "linux", not(target_env = "musl")),
+            target_os = "android",
+            target_os = "hurd"
+        )))]
         use libc::pwrite as pwrite64;
-        #[cfg(any(target_os = "linux", target_os = "android", target_os = "hurd"))]
+        #[cfg(any(
+            all(target_os = "linux", not(target_env = "musl")),
+            target_os = "android",
+            target_os = "hurd"
+        ))]
         use libc::pwrite64;
 
         unsafe {

library/std/src/sys/unix/fs.rs

@@ -40,13 +40,17 @@ use libc::{c_int, mode_t};
 ))]
 use libc::c_char;
 #[cfg(any(
-    target_os = "linux",
+    all(target_os = "linux", not(target_env = "musl")),
     target_os = "emscripten",
     target_os = "android",
-    target_os = "hurd",
+    target_os = "hurd"
 ))]
 use libc::dirfd;
-#[cfg(any(target_os = "linux", target_os = "emscripten", target_os = "hurd"))]
+#[cfg(any(
+    all(target_os = "linux", not(target_env = "musl")),
+    target_os = "emscripten",
+    target_os = "hurd"
+))]
 use libc::fstatat64;
 #[cfg(any(
     target_os = "android",
@@ -57,9 +61,10 @@ use libc::fstatat64;
     target_os = "aix",
     target_os = "nto",
     target_os = "vita",
+    all(target_os = "linux", target_env = "musl"),
 ))]
 use libc::readdir as readdir64;
-#[cfg(any(target_os = "linux", target_os = "hurd"))]
+#[cfg(any(all(target_os = "linux", not(target_env = "musl")), target_os = "hurd"))]
 use libc::readdir64;
 #[cfg(any(target_os = "emscripten", target_os = "l4re"))]
 use libc::readdir64_r;
@@ -84,7 +89,7 @@ use libc::{
     lstat as lstat64, off64_t, open as open64, stat as stat64,
 };
 #[cfg(not(any(
-    target_os = "linux",
+    all(target_os = "linux", not(target_env = "musl")),
     target_os = "emscripten",
     target_os = "l4re",
     target_os = "android",
@@ -95,7 +100,7 @@ use libc::{
     lstat as lstat64, off_t as off64_t, open as open64, stat as stat64,
 };
 #[cfg(any(
-    target_os = "linux",
+    all(target_os = "linux", not(target_env = "musl")),
     target_os = "emscripten",
     target_os = "l4re",
     target_os = "hurd"
@@ -853,10 +858,10 @@ impl DirEntry {
 
     #[cfg(all(
         any(
-            target_os = "linux",
+            all(target_os = "linux", not(target_env = "musl")),
             target_os = "emscripten",
             target_os = "android",
-            target_os = "hurd",
+            target_os = "hurd"
         ),
         not(miri)
     ))]
@@ -882,7 +887,7 @@ impl DirEntry {
 
     #[cfg(any(
         not(any(
-            target_os = "linux",
+            all(target_os = "linux", not(target_env = "musl")),
             target_os = "emscripten",
             target_os = "android",
             target_os = "hurd",

src/bootstrap/src/core/build_steps/dist.rs

@@ -1305,6 +1305,10 @@ impl Step for CodegenBackend {
             return None;
         }
 
+        if !builder.config.rust_codegen_backends.contains(&self.backend) {
+            return None;
+        }
+
         if self.backend == "cranelift" {
             if !target_supports_cranelift_backend(self.compiler.host) {
                 builder.info("target not supported by rustc_codegen_cranelift. skipping");
@@ -1343,12 +1347,15 @@ impl Step for CodegenBackend {
         let backends_dst = PathBuf::from("lib").join(&backends_rel);
 
         let backend_name = format!("rustc_codegen_{}", backend);
+        let mut found_backend = false;
         for backend in fs::read_dir(&backends_src).unwrap() {
             let file_name = backend.unwrap().file_name();
             if file_name.to_str().unwrap().contains(&backend_name) {
                 tarball.add_file(backends_src.join(file_name), &backends_dst, 0o644);
+                found_backend = true;
             }
         }
+        assert!(found_backend);
 
         Some(tarball.generate())
     }

src/bootstrap/src/core/config/config.rs

@@ -1274,8 +1274,9 @@ impl Config {
         }
 
         config.initial_rustc = if let Some(rustc) = build.rustc {
-            // FIXME(#115065): re-enable this check
-            // config.check_build_rustc_version(&rustc);
+            if !flags.skip_stage0_validation {
+                config.check_build_rustc_version(&rustc);
+            }
             PathBuf::from(rustc)
         } else {
             config.download_beta_toolchain();

src/bootstrap/src/core/config/flags.rs

@@ -155,6 +155,9 @@ pub struct Flags {
     /// Enable BOLT link flags
     #[arg(global(true), long)]
     pub enable_bolt_settings: bool,
+    /// Skip stage0 compiler validation
+    #[arg(global(true), long)]
+    pub skip_stage0_validation: bool,
     /// Additional reproducible artifacts that should be added to the reproducible artifacts archive.
     #[arg(global(true), long)]
     pub reproducible_artifact: Vec<String>,

src/ci/docker/run.sh

@@ -288,6 +288,7 @@ docker \
   --env DIST_TRY_BUILD \
   --env PR_CI_JOB \
   --env OBJDIR_ON_HOST="$objdir" \
+  --env CODEGEN_BACKENDS \
   --init \
   --rm \
   rust-ci \