diff --git a/src/libcore/Cargo.toml b/src/libcore/Cargo.toml index 0b01cfc488bba..7fd61f07d5e7f 100644 --- a/src/libcore/Cargo.toml +++ b/src/libcore/Cargo.toml @@ -21,3 +21,7 @@ path = "../libcore/benches/lib.rs" [dev-dependencies] rand = "0.5" + +[features] +# Make panics and failed asserts immediately abort without formatting any message +panic_immediate_abort = [] diff --git a/src/libcore/panicking.rs b/src/libcore/panicking.rs index 58407de9566e9..aa18a60fc0f6d 100644 --- a/src/libcore/panicking.rs +++ b/src/libcore/panicking.rs @@ -39,9 +39,16 @@ use fmt; use panic::{Location, PanicInfo}; -#[cold] #[inline(never)] // this is the slow path, always +#[cold] +// never inline unless panic_immediate_abort to avoid code +// bloat at the call sites as much as possible +#[cfg_attr(not(feature="panic_immediate_abort"),inline(never))] #[lang = "panic"] pub fn panic(expr_file_line_col: &(&'static str, &'static str, u32, u32)) -> ! { + if cfg!(feature = "panic_immediate_abort") { + unsafe { super::intrinsics::abort() } + } + // Use Arguments::new_v1 instead of format_args!("{}", expr) to potentially // reduce size overhead. The format_args! macro uses str's Display trait to // write expr, which calls Formatter::pad, which must accommodate string @@ -52,16 +59,27 @@ pub fn panic(expr_file_line_col: &(&'static str, &'static str, u32, u32)) -> ! { panic_fmt(fmt::Arguments::new_v1(&[expr], &[]), &(file, line, col)) } -#[cold] #[inline(never)] +#[cold] +#[cfg_attr(not(feature="panic_immediate_abort"),inline(never))] #[lang = "panic_bounds_check"] fn panic_bounds_check(file_line_col: &(&'static str, u32, u32), index: usize, len: usize) -> ! { + if cfg!(feature = "panic_immediate_abort") { + unsafe { super::intrinsics::abort() } + } + panic_fmt(format_args!("index out of bounds: the len is {} but the index is {}", len, index), file_line_col) } -#[cold] #[inline(never)] +#[cold] +#[cfg_attr(not(feature="panic_immediate_abort"),inline(never))] +#[cfg_attr( feature="panic_immediate_abort" ,inline)] pub fn panic_fmt(fmt: fmt::Arguments, file_line_col: &(&'static str, u32, u32)) -> ! { + if cfg!(feature = "panic_immediate_abort") { + unsafe { super::intrinsics::abort() } + } + // NOTE This function never crosses the FFI boundary; it's a Rust-to-Rust call #[allow(improper_ctypes)] // PanicInfo contains a trait object which is not FFI safe extern "Rust" { diff --git a/src/libstd/Cargo.toml b/src/libstd/Cargo.toml index 2b1d515c83b75..c1446218367e4 100644 --- a/src/libstd/Cargo.toml +++ b/src/libstd/Cargo.toml @@ -47,6 +47,9 @@ backtrace = [] panic-unwind = ["panic_unwind"] profiler = ["profiler_builtins"] +# Make panics and failed asserts immediately abort without formatting any message +panic_immediate_abort = ["core/panic_immediate_abort"] + # An off-by-default feature which enables a linux-syscall-like ABI for libstd to # interoperate with the host environment. Currently not well documented and # requires rebuilding the standard library to use it. diff --git a/src/libstd/panicking.rs b/src/libstd/panicking.rs index a0590a800d3cc..4930d35660814 100644 --- a/src/libstd/panicking.rs +++ b/src/libstd/panicking.rs @@ -334,9 +334,17 @@ pub fn rust_begin_panic(info: &PanicInfo) -> ! { #[unstable(feature = "libstd_sys_internals", reason = "used by the panic! macro", issue = "0")] -#[inline(never)] #[cold] +#[cold] +// If panic_immediate_abort, inline the abort call, +// otherwise avoid inlining because of it is cold path. +#[cfg_attr(not(feature="panic_immediate_abort"),inline(never))] +#[cfg_attr( feature="panic_immediate_abort" ,inline)] pub fn begin_panic_fmt(msg: &fmt::Arguments, file_line_col: &(&'static str, u32, u32)) -> ! { + if cfg!(feature = "panic_immediate_abort") { + unsafe { intrinsics::abort() } + } + let (file, line, col) = *file_line_col; let info = PanicInfo::internal_constructor( Some(msg), @@ -398,8 +406,15 @@ fn continue_panic_fmt(info: &PanicInfo) -> ! { reason = "used by the panic! macro", issue = "0")] #[cfg_attr(not(test), lang = "begin_panic")] -#[inline(never)] #[cold] // avoid code bloat at the call sites as much as possible +// never inline unless panic_immediate_abort to avoid code +// bloat at the call sites as much as possible +#[cfg_attr(not(feature="panic_immediate_abort"),inline(never))] +#[cold] pub fn begin_panic(msg: M, file_line_col: &(&'static str, u32, u32)) -> ! { + if cfg!(feature = "panic_immediate_abort") { + unsafe { intrinsics::abort() } + } + // 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