Add panic=immediate-abort

Author: saethlin

alloc/Cargo.toml

@@ -22,8 +22,6 @@ compiler_builtins = { path = "../compiler-builtins/compiler-builtins", features
 compiler-builtins-mem = ['compiler_builtins/mem']
 compiler-builtins-c = ["compiler_builtins/c"]
 compiler-builtins-no-f16-f128 = ["compiler_builtins/no-f16-f128"]
-# Make panics and failed asserts immediately abort without formatting any message
-panic_immediate_abort = ["core/panic_immediate_abort"]
 # Choose algorithms that are optimized for binary size instead of runtime performance
 optimize_for_size = ["core/optimize_for_size"]
 

alloc/src/alloc.rs

@@ -408,12 +408,12 @@ pub const fn handle_alloc_error(layout: Layout) -> ! {
         }
     }
 
-    #[cfg(not(feature = "panic_immediate_abort"))]
+    #[cfg(not(panic = "immediate_abort"))]
     {
         core::intrinsics::const_eval_select((layout,), ct_error, rt_error)
     }
 
-    #[cfg(feature = "panic_immediate_abort")]
+    #[cfg(panic = "immediate_abort")]
     ct_error(layout)
 }
 

alloc/src/raw_vec/mod.rs

@@ -23,7 +23,7 @@ mod tests;
 // ensure that the code generation related to these panics is minimal as there's
 // only one location which panics rather than a bunch throughout the module.
 #[cfg(not(no_global_oom_handling))]
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
 #[track_caller]
 fn capacity_overflow() -> ! {
     panic!("capacity overflow");

alloc/src/vec/mod.rs

@@ -2020,7 +2020,7 @@ impl<T, A: Allocator> Vec<T, A> {
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn swap_remove(&mut self, index: usize) -> T {
         #[cold]
-        #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+        #[cfg_attr(not(panic = "immediate_abort"), inline(never))]
         #[track_caller]
         #[optimize(size)]
         fn assert_failed(index: usize, len: usize) -> ! {
@@ -2102,7 +2102,7 @@ impl<T, A: Allocator> Vec<T, A> {
     #[must_use = "if you don't need a reference to the value, use `Vec::insert` instead"]
     pub fn insert_mut(&mut self, index: usize, element: T) -> &mut T {
         #[cold]
-        #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+        #[cfg_attr(not(panic = "immediate_abort"), inline(never))]
         #[track_caller]
         #[optimize(size)]
         fn assert_failed(index: usize, len: usize) -> ! {
@@ -2166,7 +2166,7 @@ impl<T, A: Allocator> Vec<T, A> {
     #[rustc_confusables("delete", "take")]
     pub fn remove(&mut self, index: usize) -> T {
         #[cold]
-        #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+        #[cfg_attr(not(panic = "immediate_abort"), inline(never))]
         #[track_caller]
         #[optimize(size)]
         fn assert_failed(index: usize, len: usize) -> ! {
@@ -2955,7 +2955,7 @@ impl<T, A: Allocator> Vec<T, A> {
         A: Clone,
     {
         #[cold]
-        #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+        #[cfg_attr(not(panic = "immediate_abort"), inline(never))]
         #[track_caller]
         #[optimize(size)]
         fn assert_failed(at: usize, len: usize) -> ! {

core/Cargo.toml

@@ -16,7 +16,7 @@ test = false
 bench = false
 
 [features]
-# Make panics and failed asserts immediately abort without formatting any message
+# Issue a compile error that says to use -Cpanic=immediate-abort
 panic_immediate_abort = []
 # Choose algorithms that are optimized for binary size instead of runtime performance
 optimize_for_size = []

core/src/cell.rs

@@ -778,7 +778,7 @@ impl Display for BorrowMutError {
 }
 
 // This ensures the panicking code is outlined from `borrow_mut` for `RefCell`.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
 #[track_caller]
 #[cold]
 const fn panic_already_borrowed(err: BorrowMutError) -> ! {
@@ -790,7 +790,7 @@ const fn panic_already_borrowed(err: BorrowMutError) -> ! {
 }
 
 // This ensures the panicking code is outlined from `borrow` for `RefCell`.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
 #[track_caller]
 #[cold]
 const fn panic_already_mutably_borrowed(err: BorrowError) -> ! {

core/src/num/mod.rs

@@ -1387,8 +1387,8 @@ pub const fn can_not_overflow<T>(radix: u32, is_signed_ty: bool, digits: &[u8])
     radix <= 16 && digits.len() <= size_of::<T>() * 2 - is_signed_ty as usize
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[cold]
 #[track_caller]
 const fn from_ascii_radix_panic(radix: u32) -> ! {

core/src/option.rs

@@ -2161,17 +2161,17 @@ impl<T, E> Option<Result<T, E>> {
     }
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[cold]
 #[track_caller]
 const fn unwrap_failed() -> ! {
     panic("called `Option::unwrap()` on a `None` value")
 }
 
 // This is a separate function to reduce the code size of .expect() itself.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[cold]
 #[track_caller]
 const fn expect_failed(msg: &str) -> ! {

core/src/panicking.rs

@@ -33,7 +33,10 @@ use crate::intrinsics::const_eval_select;
 use crate::panic::{Location, PanicInfo};
 
 #[cfg(feature = "panic_immediate_abort")]
-const _: () = assert!(cfg!(panic = "abort"), "panic_immediate_abort requires -C panic=abort");
+compile_error!(
+    "panic_immediate_abort is now a real panic strategy! \
+    Enable it with the compiler flags `-Zunstable-options -Cpanic=immediate-abort`"
+);
 
 // First we define the two main entry points that all panics go through.
 // In the end both are just convenience wrappers around `panic_impl`.
@@ -44,16 +47,16 @@ const _: () = assert!(cfg!(panic = "abort"), "panic_immediate_abort requires -C
 /// site as much as possible (so that `panic!()` has as low an impact
 /// on (e.g.) the inlining of other functions as possible), by moving
 /// the actual formatting into this shared place.
-// If panic_immediate_abort, inline the abort call,
+// 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), cold)]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[lang = "panic_fmt"] // needed for const-evaluated panics
 #[rustc_do_not_const_check] // hooked by const-eval
 #[rustc_const_stable_indirect] // must follow stable const rules since it is exposed to stable
 pub const fn panic_fmt(fmt: fmt::Arguments<'_>) -> ! {
-    if cfg!(feature = "panic_immediate_abort") {
+    if cfg!(panic = "immediate_abort") {
         super::intrinsics::abort()
     }
 
@@ -78,8 +81,8 @@ pub const fn panic_fmt(fmt: fmt::Arguments<'_>) -> ! {
 /// Like `panic_fmt`, but for non-unwinding panics.
 ///
 /// Has to be a separate function so that it can carry the `rustc_nounwind` attribute.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 // This attribute has the key side-effect that if the panic handler ignores `can_unwind`
 // and unwinds anyway, we will hit the "unwinding out of nounwind function" guard,
@@ -94,7 +97,7 @@ pub const fn panic_nounwind_fmt(fmt: fmt::Arguments<'_>, force_no_backtrace: boo
             // We don't unwind anyway at compile-time so we can call the regular `panic_fmt`.
             panic_fmt(fmt)
         } else #[track_caller] {
-            if cfg!(feature = "panic_immediate_abort") {
+            if cfg!(panic = "immediate_abort") {
                 super::intrinsics::abort()
             }
 
@@ -123,10 +126,10 @@ pub const fn panic_nounwind_fmt(fmt: fmt::Arguments<'_>, force_no_backtrace: boo
 // above.
 
 /// The underlying implementation of core's `panic!` macro when no formatting is used.
-// Never inline unless panic_immediate_abort to avoid code
+// 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)]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[rustc_const_stable_indirect] // must follow stable const rules since it is exposed to stable
 #[lang = "panic"] // used by lints and miri for panics
@@ -158,10 +161,10 @@ macro_rules! panic_const {
         $(
             /// This is a panic called with a message that's a result of a MIR-produced Assert.
             //
-            // never inline unless panic_immediate_abort to avoid code
+            // never inline unless panic=immediate-abort to avoid code
             // bloat at the call sites as much as possible
-            #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
-            #[cfg_attr(feature = "panic_immediate_abort", inline)]
+            #[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+            #[cfg_attr(panic = "immediate_abort", inline)]
             #[track_caller]
             #[rustc_const_stable_indirect] // must follow stable const rules since it is exposed to stable
             #[lang = stringify!($lang)]
@@ -216,8 +219,8 @@ pub mod panic_const {
 
 /// Like `panic`, but without unwinding and track_caller to reduce the impact on codesize on the caller.
 /// If you want `#[track_caller]` for nicer errors, call `panic_nounwind_fmt` directly.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[lang = "panic_nounwind"] // needed by codegen for non-unwinding panics
 #[rustc_nounwind]
 #[rustc_const_stable_indirect] // must follow stable const rules since it is exposed to stable
@@ -226,8 +229,8 @@ pub const fn panic_nounwind(expr: &'static str) -> ! {
 }
 
 /// Like `panic_nounwind`, but also inhibits showing a backtrace.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold)]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[rustc_nounwind]
 pub fn panic_nounwind_nobacktrace(expr: &'static str) -> ! {
     panic_nounwind_fmt(fmt::Arguments::new_const(&[expr]), /* force_no_backtrace */ true);
@@ -259,25 +262,25 @@ pub const fn panic_display<T: fmt::Display>(x: &T) -> ! {
     panic_fmt(format_args!("{}", *x));
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[lang = "panic_bounds_check"] // needed by codegen for panic on OOB array/slice access
 fn panic_bounds_check(index: usize, len: usize) -> ! {
-    if cfg!(feature = "panic_immediate_abort") {
+    if cfg!(panic = "immediate_abort") {
         super::intrinsics::abort()
     }
 
     panic!("index out of bounds: the len is {len} but the index is {index}")
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[lang = "panic_misaligned_pointer_dereference"] // needed by codegen for panic on misaligned pointer deref
 #[rustc_nounwind] // `CheckAlignment` MIR pass requires this function to never unwind
 fn panic_misaligned_pointer_dereference(required: usize, found: usize) -> ! {
-    if cfg!(feature = "panic_immediate_abort") {
+    if cfg!(panic = "immediate_abort") {
         super::intrinsics::abort()
     }
 
@@ -289,13 +292,13 @@ fn panic_misaligned_pointer_dereference(required: usize, found: usize) -> ! {
     )
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[lang = "panic_null_pointer_dereference"] // needed by codegen for panic on null pointer deref
 #[rustc_nounwind] // `CheckNull` MIR pass requires this function to never unwind
 fn panic_null_pointer_dereference() -> ! {
-    if cfg!(feature = "panic_immediate_abort") {
+    if cfg!(panic = "immediate_abort") {
         super::intrinsics::abort()
     }
 
@@ -305,13 +308,13 @@ fn panic_null_pointer_dereference() -> ! {
     )
 }
 
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[lang = "panic_invalid_enum_construction"] // needed by codegen for panic on invalid enum construction.
 #[rustc_nounwind] // `CheckEnums` MIR pass requires this function to never unwind
 fn panic_invalid_enum_construction(source: u128) -> ! {
-    if cfg!(feature = "panic_immediate_abort") {
+    if cfg!(panic = "immediate_abort") {
         super::intrinsics::abort()
     }
 
@@ -328,8 +331,8 @@ fn panic_invalid_enum_construction(source: u128) -> ! {
 ///
 /// This function is called directly by the codegen backend, and must not have
 /// any extra arguments (including those synthesized by track_caller).
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[lang = "panic_cannot_unwind"] // needed by codegen for panic in nounwind function
 #[rustc_nounwind]
 fn panic_cannot_unwind() -> ! {
@@ -344,8 +347,8 @@ fn panic_cannot_unwind() -> ! {
 ///
 /// This function is called directly by the codegen backend, and must not have
 /// any extra arguments (including those synthesized by track_caller).
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[lang = "panic_in_cleanup"] // needed by codegen for panic in nounwind function
 #[rustc_nounwind]
 fn panic_in_cleanup() -> ! {
@@ -377,8 +380,8 @@ pub enum AssertKind {
 }
 
 /// Internal function for `assert_eq!` and `assert_ne!` macros
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[doc(hidden)]
 pub fn assert_failed<T, U>(
@@ -395,8 +398,8 @@ where
 }
 
 /// Internal function for `assert_match!`
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 #[doc(hidden)]
 pub fn assert_matches_failed<T: fmt::Debug + ?Sized>(
@@ -415,8 +418,8 @@ pub fn assert_matches_failed<T: fmt::Debug + ?Sized>(
 }
 
 /// Non-generic version of the above functions, to avoid code bloat.
-#[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold, optimize(size))]
-#[cfg_attr(feature = "panic_immediate_abort", inline)]
+#[cfg_attr(not(panic = "immediate_abort"), inline(never), cold, optimize(size))]
+#[cfg_attr(panic = "immediate_abort", inline)]
 #[track_caller]
 fn assert_failed_inner(
     kind: AssertKind,

core/src/result.rs

@@ -1847,7 +1847,7 @@ impl<T, E> Result<Result<T, E>, E> {
 }
 
 // This is a separate function to reduce the code size of the methods
-#[cfg(not(feature = "panic_immediate_abort"))]
+#[cfg(not(panic = "immediate_abort"))]
 #[inline(never)]
 #[cold]
 #[track_caller]
@@ -1859,7 +1859,7 @@ fn unwrap_failed(msg: &str, error: &dyn fmt::Debug) -> ! {
 // that gets immediately thrown away, since vtables don't get cleaned up
 // by dead code elimination if a trait object is constructed even if it goes
 // unused
-#[cfg(feature = "panic_immediate_abort")]
+#[cfg(panic = "immediate_abort")]
 #[inline]
 #[cold]
 #[track_caller]