diff options
| -rw-r--r-- | library/alloc/Cargo.toml | 3 | ||||
| -rw-r--r-- | library/alloc/src/alloc.rs | 84 | ||||
| -rw-r--r-- | library/alloc/src/lib.rs | 1 | ||||
| -rw-r--r-- | library/std/Cargo.toml | 2 | ||||
| -rw-r--r-- | library/std/src/lib.rs | 1 | ||||
| -rw-r--r-- | library/std/src/panicking.rs | 43 |
6 files changed, 27 insertions, 107 deletions
diff --git a/library/alloc/Cargo.toml b/library/alloc/Cargo.toml index 8975ba3f06b..95c07abf731 100644 --- a/library/alloc/Cargo.toml +++ b/library/alloc/Cargo.toml @@ -35,6 +35,3 @@ compiler-builtins-mem = ['compiler_builtins/mem'] compiler-builtins-c = ["compiler_builtins/c"] compiler-builtins-no-asm = ["compiler_builtins/no-asm"] compiler-builtins-mangled-names = ["compiler_builtins/mangled-names"] - -# Make panics and failed asserts immediately abort without formatting any message -panic_immediate_abort = ["core/panic_immediate_abort"] diff --git a/library/alloc/src/alloc.rs b/library/alloc/src/alloc.rs index 08c65a96bc7..6f2ba957bcd 100644 --- a/library/alloc/src/alloc.rs +++ b/library/alloc/src/alloc.rs @@ -14,11 +14,6 @@ use core::ptr::{self, NonNull}; #[doc(inline)] pub use core::alloc::*; -#[cfg(not(no_global_oom_handling))] -use core::any::Any; -#[cfg(not(no_global_oom_handling))] -use core::panic::BoxMeUp; - #[cfg(test)] mod tests; @@ -348,77 +343,14 @@ pub(crate) unsafe fn box_free<T: ?Sized, A: Allocator>(ptr: Unique<T>, alloc: A) } } -/// Payload passed to the panic handler when `handle_alloc_error` is called. -#[unstable(feature = "panic_oom_payload", issue = "none")] -#[derive(Debug)] -pub struct AllocErrorPanicPayload { - layout: Layout, -} - -impl AllocErrorPanicPayload { - /// Internal function for the standard library to clone a payload. - #[unstable(feature = "std_internals", issue = "none")] - #[doc(hidden)] - pub fn internal_clone(&self) -> Self { - AllocErrorPanicPayload { layout: self.layout } - } - - /// Returns the [`Layout`] of the allocation attempt that caused the error. - #[unstable(feature = "panic_oom_payload", issue = "none")] - pub fn layout(&self) -> Layout { - self.layout - } -} - -#[unstable(feature = "std_internals", issue = "none")] -#[cfg(not(no_global_oom_handling))] -unsafe impl BoxMeUp for AllocErrorPanicPayload { - fn take_box(&mut self) -> *mut (dyn Any + Send) { - use crate::boxed::Box; - Box::into_raw(Box::new(self.internal_clone())) - } - - fn get(&mut self) -> &(dyn Any + Send) { - self - } -} - // # Allocation error handler -#[cfg(all(not(no_global_oom_handling), not(test)))] -fn rust_oom(layout: Layout) -> ! { - if cfg!(feature = "panic_immediate_abort") { - core::intrinsics::abort() - } - - extern "Rust" { - // NOTE This function never crosses the FFI boundary; it's a Rust-to-Rust call - // that gets resolved to the `#[panic_handler]` function. - #[lang = "panic_impl"] - fn panic_impl(pi: &core::panic::PanicInfo<'_>) -> !; - - // This symbol is emitted by rustc next to __rust_alloc_error_handler. - // Its value depends on the -Zoom={panic,abort} compiler option. - static __rust_alloc_error_handler_should_panic: u8; - } - - // Hack to work around issues with the lifetime of Arguments. - match format_args!("memory allocation of {} bytes failed", layout.size()) { - fmt => { - // Create a PanicInfo with a custom payload for the panic handler. - let can_unwind = unsafe { __rust_alloc_error_handler_should_panic != 0 }; - let mut pi = core::panic::PanicInfo::internal_constructor( - Some(&fmt), - core::panic::Location::caller(), - can_unwind, - ); - let payload = AllocErrorPanicPayload { layout }; - pi.set_payload(&payload); - - // SAFETY: `panic_impl` is defined in safe Rust code and thus is safe to call. - unsafe { panic_impl(&pi) } - } - } +#[cfg(not(no_global_oom_handling))] +extern "Rust" { + // This is the magic symbol to call the global alloc error handler. rustc generates + // it to call `__rg_oom` if there is a `#[alloc_error_handler]`, or to call the + // default implementations below (`__rdl_oom`) otherwise. + fn __rust_alloc_error_handler(size: usize, align: usize) -> !; } /// Abort on memory allocation error or failure. @@ -443,7 +375,9 @@ pub const fn handle_alloc_error(layout: Layout) -> ! { } fn rt_error(layout: Layout) -> ! { - rust_oom(layout); + unsafe { + __rust_alloc_error_handler(layout.size(), layout.align()); + } } unsafe { core::intrinsics::const_eval_select((layout,), ct_error, rt_error) } diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs index 2c6a266e2a1..a002421aeef 100644 --- a/library/alloc/src/lib.rs +++ b/library/alloc/src/lib.rs @@ -135,7 +135,6 @@ #![feature(maybe_uninit_slice)] #![feature(maybe_uninit_uninit_array)] #![feature(maybe_uninit_uninit_array_transpose)] -#![feature(panic_internals)] #![feature(pattern)] #![feature(pointer_byte_offsets)] #![feature(provide_any)] diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml index 109387b09d0..f2fda64a1ee 100644 --- a/library/std/Cargo.toml +++ b/library/std/Cargo.toml @@ -67,7 +67,7 @@ llvm-libunwind = ["unwind/llvm-libunwind"] system-llvm-libunwind = ["unwind/system-llvm-libunwind"] # Make panics and failed asserts immediately abort without formatting any message -panic_immediate_abort = ["alloc/panic_immediate_abort"] +panic_immediate_abort = ["core/panic_immediate_abort"] # Enable std_detect default features for stdarch/crates/std_detect: # https://github.com/rust-lang/stdarch/blob/master/crates/std_detect/Cargo.toml diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs index 31400aa1820..318a46d1b63 100644 --- a/library/std/src/lib.rs +++ b/library/std/src/lib.rs @@ -320,7 +320,6 @@ #![feature(get_mut_unchecked)] #![feature(map_try_insert)] #![feature(new_uninit)] -#![feature(panic_oom_payload)] #![feature(slice_concat_trait)] #![feature(thin_box)] #![feature(try_reserve_kind)] diff --git a/library/std/src/panicking.rs b/library/std/src/panicking.rs index ca4cf68ad54..a46a29cbad6 100644 --- a/library/std/src/panicking.rs +++ b/library/std/src/panicking.rs @@ -245,24 +245,19 @@ fn default_hook(info: &PanicInfo<'_>) { // The current implementation always returns `Some`. let location = info.location().unwrap(); + + let msg = match info.payload().downcast_ref::<&'static str>() { + Some(s) => *s, + None => match info.payload().downcast_ref::<String>() { + Some(s) => &s[..], + None => "Box<dyn Any>", + }, + }; let thread = thread_info::current_thread(); let name = thread.as_ref().and_then(|t| t.name()).unwrap_or("<unnamed>"); let write = |err: &mut dyn crate::io::Write| { - // Use the panic message directly if available, otherwise take it from - // the payload. - if let Some(msg) = info.message() { - let _ = writeln!(err, "thread '{name}' panicked at '{msg}', {location}"); - } else { - let msg = if let Some(s) = info.payload().downcast_ref::<&'static str>() { - *s - } else if let Some(s) = info.payload().downcast_ref::<String>() { - &s[..] - } else { - "Box<dyn Any>" - }; - let _ = writeln!(err, "thread '{name}' panicked at '{msg}', {location}"); - } + let _ = writeln!(err, "thread '{name}' panicked at '{msg}', {location}"); static FIRST_PANIC: AtomicBool = AtomicBool::new(true); @@ -529,8 +524,6 @@ pub fn panicking() -> bool { #[cfg(not(test))] #[panic_handler] pub fn begin_panic_handler(info: &PanicInfo<'_>) -> ! { - use alloc::alloc::AllocErrorPanicPayload; - struct PanicPayload<'a> { inner: &'a fmt::Arguments<'a>, string: Option<String>, @@ -557,7 +550,8 @@ pub fn begin_panic_handler(info: &PanicInfo<'_>) -> ! { unsafe impl<'a> BoxMeUp for PanicPayload<'a> { fn take_box(&mut self) -> *mut (dyn Any + Send) { // We do two allocations here, unfortunately. But (a) they're required with the current - // scheme, and (b) OOM uses its own separate payload type which doesn't allocate. + // scheme, and (b) we don't handle panic + OOM properly anyway (see comment in + // begin_panic below). let contents = mem::take(self.fill()); Box::into_raw(Box::new(contents)) } @@ -582,14 +576,7 @@ pub fn begin_panic_handler(info: &PanicInfo<'_>) -> ! { let loc = info.location().unwrap(); // The current implementation always returns Some let msg = info.message().unwrap(); // The current implementation always returns Some crate::sys_common::backtrace::__rust_end_short_backtrace(move || { - if let Some(payload) = info.payload().downcast_ref::<AllocErrorPanicPayload>() { - rust_panic_with_hook( - &mut payload.internal_clone(), - info.message(), - loc, - info.can_unwind(), - ); - } else if let Some(msg) = msg.as_str() { + if let Some(msg) = msg.as_str() { rust_panic_with_hook(&mut StrPanicPayload(msg), info.message(), loc, info.can_unwind()); } else { rust_panic_with_hook( @@ -636,7 +623,11 @@ pub const fn begin_panic<M: Any + Send>(msg: M) -> ! { unsafe impl<A: Send + 'static> BoxMeUp for PanicPayload<A> { fn take_box(&mut self) -> *mut (dyn Any + Send) { - // Note that this should be the only allocation performed in this code path. + // Note that this should be the only allocation performed in this code path. Currently + // this means that panic!() on OOM will invoke this code path, but then again we're not + // really ready for panic on OOM anyway. If we do start doing this, then we should + // propagate this allocation to be performed in the parent of this thread instead of the + // thread that's panicking. let data = match self.inner.take() { Some(a) => Box::new(a) as Box<dyn Any + Send>, None => process::abort(), |