Rollup of 7 pull requests

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -32,7 +32,7 @@ use tracing::debug;
 
 use crate::Namespace::{MacroNS, TypeNS, ValueNS};
 use crate::def_collector::DefCollector;
-use crate::error_helper::{OnUnknownData, StructCtor};
+use crate::diagnostics::impls::{OnUnknownData, StructCtor};
 use crate::imports::{ImportData, ImportKind, NameResolution, NameResolutionRef};
 use crate::macros::{MacroRulesDecl, MacroRulesScope, MacroRulesScopeRef};
 use crate::ref_mut::CmCell;

compiler/rustc_resolve/src/diagnostics.rs → compiler/rustc_resolve/src/diagnostics/mod.rs

@@ -10,6 +10,8 @@ use rustc_span::{Ident, Span, Spanned, Symbol};
 use crate::Res;
 use crate::late::{PatternSource, ResolvingRestrictionKind};
 
+pub(crate) mod impls;
+
 #[derive(Diagnostic)]
 #[diag("can't use {$is_self ->
         [true] `Self`

compiler/rustc_resolve/src/imports.rs

@@ -25,13 +25,13 @@ use rustc_span::{Ident, Span, Symbol, kw, sym};
 use tracing::debug;
 
 use crate::Namespace::{self, *};
+use crate::diagnostics::impls::{OnUnknownData, Suggestion};
 use crate::diagnostics::{
     self, CannotBeReexportedCratePublic, CannotBeReexportedCratePublicNS,
     CannotBeReexportedPrivate, CannotBeReexportedPrivateNS, CannotDetermineImportResolution,
     CannotGlobImportAllCrates, ConsiderAddingMacroExport, ConsiderMarkingAsPub,
     ConsiderMarkingAsPubCrate,
 };
-use crate::error_helper::{OnUnknownData, Suggestion};
 use crate::ref_mut::{CmCell, CmRefCell};
 use crate::{
     AmbiguityError, BindingKey, CmResolver, Decl, DeclData, DeclKind, Determinacy, Finalize,

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -32,7 +32,7 @@ use thin_vec::{ThinVec, thin_vec};
 use tracing::debug;
 
 use super::NoConstantGenericsReason;
-use crate::error_helper::{ImportSuggestion, LabelSuggestion, TypoSuggestion};
+use crate::diagnostics::impls::{ImportSuggestion, LabelSuggestion, TypoSuggestion};
 use crate::late::{
     AliasPossibility, LateResolutionVisitor, LifetimeBinderKind, LifetimeRes, LifetimeRibKind,
     LifetimeUseSet, QSelf, RibKind,

compiler/rustc_resolve/src/lib.rs

@@ -29,7 +29,6 @@ use std::{fmt, mem};
 
 use diagnostics::{ParamKindInEnumDiscriminant, ParamKindInNonTrivialAnonConst};
 use effective_visibilities::EffectiveVisibilitiesVisitor;
-use error_helper::{ImportSuggestion, LabelSuggestion, StructCtor, Suggestion};
 use hygiene::Macros20NormalizedSyntaxContext;
 use imports::{Import, ImportData, ImportKind, NameResolution, PendingDecl};
 use late::{
@@ -77,7 +76,9 @@ use rustc_span::{DUMMY_SP, Ident, Span, Symbol, kw, sym};
 use smallvec::{SmallVec, smallvec};
 use tracing::{debug, instrument};
 
-use crate::error_helper::OnUnknownData;
+use crate::diagnostics::impls::{
+    ImportSuggestion, LabelSuggestion, OnUnknownData, StructCtor, Suggestion,
+};
 use crate::imports::NameResolutionRef;
 use crate::ref_mut::{CmCell, CmRefCell};
 
@@ -86,7 +87,6 @@ mod check_unused;
 mod def_collector;
 mod diagnostics;
 mod effective_visibilities;
-mod error_helper;
 mod ident;
 mod imports;
 mod late;

library/panic_unwind/src/gcc.rs

@@ -60,11 +60,7 @@ struct Exception {
 
 pub(crate) unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
     let exception = Box::new(Exception {
-        _uwe: uw::_Unwind_Exception {
-            exception_class: RUST_EXCEPTION_CLASS,
-            exception_cleanup: Some(exception_cleanup),
-            private: [core::ptr::null(); uw::unwinder_private_data_size],
-        },
+        _uwe: uw::_Unwind_Exception::new(RUST_EXCEPTION_CLASS, Some(exception_cleanup)),
         canary: &CANARY,
         cause: data,
     });

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

@@ -38,21 +38,19 @@ pub unsafe fn environ() -> *mut *const *const c_char {
     unsafe { libc::_NSGetEnviron() as *mut *const *const c_char }
 }
 
-// On FreeBSD, environ comes from CRT rather than libc
+// On FreeBSD, environ lives in crt1.o, not libc.so, so a shared library
+// cannot take a strong link-time reference to it (#153451), and dlsym cannot
+// find it in a statically linked executable, which has no dynamic symbol
+// table to search (#158939). A weak reference covers both: it binds at link
+// time in any executable, and in a shared library the runtime linker
+// resolves it against the environ the executable exports.
 #[cfg(target_os = "freebsd")]
 pub unsafe fn environ() -> *mut *const *const c_char {
-    use crate::sync::LazyLock;
-
-    struct Environ(*mut *const *const c_char);
-    unsafe impl Send for Environ {}
-    unsafe impl Sync for Environ {}
-
-    static ENVIRON: LazyLock<Environ> = LazyLock::new(|| {
-        Environ(unsafe {
-            libc::dlsym(libc::RTLD_DEFAULT, c"environ".as_ptr()) as *mut *const *const c_char
-        })
-    });
-    ENVIRON.0
+    unsafe extern "C" {
+        #[linkage = "extern_weak"]
+        static environ: *mut *const *const c_char;
+    }
+    unsafe { environ }
 }
 
 // Use the `environ` static which is part of POSIX.
@@ -75,14 +73,19 @@ pub fn env_read_lock() -> impl Drop {
 pub fn env() -> Env {
     unsafe {
         let _guard = env_read_lock();
-        let mut environ = *environ();
         let mut result = Vec::new();
-        if !environ.is_null() {
-            while !(*environ).is_null() {
-                if let Some(key_value) = parse(CStr::from_ptr(*environ).to_bytes()) {
-                    result.push(key_value);
+        // A null return means the platform could not locate the symbol;
+        // treat it like an empty environment.
+        let environ_ptr = environ();
+        if !environ_ptr.is_null() {
+            let mut environ = *environ_ptr;
+            if !environ.is_null() {
+                while !(*environ).is_null() {
+                    if let Some(key_value) = parse(CStr::from_ptr(*environ).to_bytes()) {
+                        result.push(key_value);
+                    }
+                    environ = environ.add(1);
                 }
-                environ = environ.add(1);
             }
         }
         return Env::new(result);

library/std/src/sys/stdio/windows.rs

@@ -278,7 +278,7 @@ impl io::Read for Stdin {
             Ok(bytes_copied)
         } else if buf.len() - bytes_copied < 4 {
             // Not enough space to get a UTF-8 byte. We will use the incomplete UTF8.
-            let mut utf16_buf = [MaybeUninit::new(0); 1];
+            let mut utf16_buf = [MaybeUninit::new(0); 2];
             // Read one u16 character.
             let read = read_u16s_fixup_surrogates(handle, &mut utf16_buf, 1, &mut self.surrogate)?;
             // Read bytes, using the (now-empty) self.incomplete_utf8 as extra space.

library/unwind/Cargo.toml

@@ -4,9 +4,6 @@ version = "0.0.0"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/rust-lang/rust.git"
 edition = "2024"
-include = [
-  '/libunwind/*',
-]
 
 [lib]
 test = false

library/unwind/src/lib.rs

@@ -33,14 +33,11 @@ cfg_select! {
         target_os = "solid_asp3",
         all(target_vendor = "fortanix", target_env = "sgx"),
         all(target_os = "wasi", panic = "unwind"),
+        target_os = "xous",
     ) => {
         mod libunwind;
         pub use libunwind::*;
     }
-    target_os = "xous" => {
-        mod unwinding;
-        pub use unwinding::*;
-    }
     target_family = "wasm" => {
         mod wasm;
         pub use wasm::*;

library/unwind/src/libunwind.rs

@@ -2,6 +2,12 @@
 
 use core::ffi::{c_int, c_void};
 
+// Use the unwinding crate as unwinder on Xous
+#[cfg(target_os = "xous")]
+pub use unwinding::custom_eh_frame_finder::{
+    EhFrameFinder, FrameInfo, FrameInfoKind, set_custom_eh_frame_finder,
+};
+
 #[repr(C)]
 #[derive(Debug, Copy, Clone, PartialEq)]
 pub enum _Unwind_Reason_Code {
@@ -24,73 +30,51 @@ pub type _Unwind_Ptr = *const u8;
 pub type _Unwind_Trace_Fn =
     extern "C" fn(ctx: *mut _Unwind_Context, arg: *mut c_void) -> _Unwind_Reason_Code;
 
-#[cfg(target_arch = "x86")]
-pub const unwinder_private_data_size: usize = 5;
-
-#[cfg(all(target_arch = "x86_64", not(any(target_os = "windows", target_os = "cygwin"))))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(all(target_arch = "x86_64", any(target_os = "windows", target_os = "cygwin")))]
-pub const unwinder_private_data_size: usize = 6;
-
-#[cfg(all(target_arch = "arm", not(target_vendor = "apple")))]
-pub const unwinder_private_data_size: usize = 20;
-
-#[cfg(all(target_arch = "arm", target_vendor = "apple"))]
-pub const unwinder_private_data_size: usize = 5;
-
-#[cfg(all(target_arch = "aarch64", target_pointer_width = "64", not(target_os = "windows")))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(all(target_arch = "aarch64", target_pointer_width = "64", target_os = "windows"))]
-pub const unwinder_private_data_size: usize = 6;
-
-#[cfg(all(target_arch = "aarch64", target_pointer_width = "32"))]
-pub const unwinder_private_data_size: usize = 5;
-
-#[cfg(target_arch = "m68k")]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(any(target_arch = "mips", target_arch = "mips32r6"))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(target_arch = "csky")]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(any(target_arch = "mips64", target_arch = "mips64r6"))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(target_arch = "s390x")]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(any(target_arch = "sparc", target_arch = "sparc64"))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(any(target_arch = "riscv64", target_arch = "riscv32"))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(all(target_family = "wasm", target_os = "emscripten"))]
-pub const unwinder_private_data_size: usize = 20;
-
-#[cfg(all(target_arch = "wasm32", any(target_os = "linux", target_os = "wasi")))]
-pub const unwinder_private_data_size: usize = 2;
-
-#[cfg(target_arch = "hexagon")]
-pub const unwinder_private_data_size: usize = 5;
-
-#[cfg(any(target_arch = "loongarch32", target_arch = "loongarch64"))]
-pub const unwinder_private_data_size: usize = 2;
+const unwinder_private_data_size: usize = cfg_select! {
+    target_arch = "x86" => 5,
+    all(target_arch = "x86_64", not(any(target_os = "windows", target_os = "cygwin"))) => 2,
+    all(target_arch = "x86_64", any(target_os = "windows", target_os = "cygwin")) => 6,
+    all(target_arch = "arm", not(target_vendor = "apple")) => 20,
+    all(target_arch = "arm", target_vendor = "apple") => 5,
+    all(target_arch = "aarch64", target_pointer_width = "64", not(target_os = "windows")) => 2,
+    all(target_arch = "aarch64", target_pointer_width = "64", target_os = "windows") => 6,
+    all(target_arch = "aarch64", target_pointer_width = "32") => 5,
+    target_arch = "m68k" => 2,
+    any(target_arch = "mips", target_arch = "mips32r6") => 2,
+    target_arch = "csky" => 2,
+    any(target_arch = "mips64", target_arch = "mips64r6") => 2,
+    any(target_arch = "powerpc", target_arch = "powerpc64") => 2,
+    target_arch = "s390x" => 2,
+    any(target_arch = "sparc", target_arch = "sparc64") => 2,
+    any(target_arch = "riscv64", target_arch = "riscv32") => 2,
+    all(target_family = "wasm", target_os = "emscripten") => 20,
+    all(target_arch = "wasm32", any(target_os = "linux", target_os = "wasi")) => 2,
+    target_arch = "hexagon" => 5,
+    any(target_arch = "loongarch32", target_arch = "loongarch64") => 2,
+};
 
 #[repr(C)]
 pub struct _Unwind_Exception {
     pub exception_class: _Unwind_Exception_Class,
     pub exception_cleanup: _Unwind_Exception_Cleanup_Fn,
-    pub private: [_Unwind_Word; unwinder_private_data_size],
+    private: [_Unwind_Word; unwinder_private_data_size],
+}
+
+impl _Unwind_Exception {
+    pub fn new(
+        exception_class: _Unwind_Exception_Class,
+        exception_cleanup: _Unwind_Exception_Cleanup_Fn,
+    ) -> Self {
+        Self { exception_class, exception_cleanup, private: [core::ptr::null(); _] }
+    }
 }
 
+// Check the size of _Unwind_Exception against the source of thruth when using the unwinding crate.
+#[cfg(target_os = "xous")]
+const _: () = {
+    assert!(size_of::<unwinding::abi::UnwindException>() == size_of::<_Unwind_Exception>());
+};
+
 pub enum _Unwind_Context {}
 
 pub type _Unwind_Exception_Cleanup_Fn =
@@ -105,10 +89,7 @@ pub type _Unwind_Exception_Cleanup_Fn =
 // rustc_codegen_ssa::src::back::symbol_export, rustc_middle::middle::exported_symbols
 // and RFC 2841
 #[cfg_attr(
-    all(
-        feature = "llvm-libunwind",
-        any(target_os = "fuchsia", target_os = "linux", target_os = "xous")
-    ),
+    all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
     link(name = "unwind", kind = "static", modifiers = "-bundle")
 )]
 // Explicitly link the `unwind` library on WASI targets.
@@ -144,7 +125,7 @@ cfg_select! {
         pub const _UA_END_OF_STACK: c_int = 16;
 
         #[cfg_attr(
-            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux", target_os = "xous")),
+            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
             link(name = "unwind", kind = "static", modifiers = "-bundle")
         )]
         unsafe extern "C" {
@@ -203,7 +184,7 @@ cfg_select! {
         pub const UNWIND_IP_REG: c_int = 15;
 
         #[cfg_attr(
-            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux", target_os = "xous")),
+            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
             link(name = "unwind", kind = "static", modifiers = "-bundle")
         )]
         unsafe extern "C" {
@@ -283,14 +264,14 @@ cfg_select! {
     }
     _ => {
         #[cfg_attr(
-            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux", target_os = "xous")),
+            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
             link(name = "unwind", kind = "static", modifiers = "-bundle")
         )]
         unsafe extern "C-unwind" {
             pub fn _Unwind_RaiseException(exception: *mut _Unwind_Exception) -> _Unwind_Reason_Code;
         }
         #[cfg_attr(
-            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux", target_os = "xous")),
+            all(feature = "llvm-libunwind", any(target_os = "fuchsia", target_os = "linux")),
             link(name = "unwind", kind = "static", modifiers = "-bundle")
         )]
         unsafe extern "C" {