Back up to just addding track_caller to panic_nounwind

Author: saethlin

library/core/src/alloc/layout.rs

@@ -123,7 +123,6 @@ impl Layout {
     #[must_use]
     #[inline]
     #[rustc_allow_const_fn_unstable(ptr_alignment_type)]
-    #[track_caller]
     pub const unsafe fn from_size_align_unchecked(size: usize, align: usize) -> Self {
         assert_unsafe_precondition!(
             check_library_ub,

library/core/src/ascii/ascii_char.rs

@@ -503,7 +503,6 @@ impl AsciiChar {
     /// something useful. It might be tightened before stabilization.)
     #[unstable(feature = "ascii_char", issue = "110998")]
     #[inline]
-    #[track_caller]
     pub const unsafe fn digit_unchecked(d: u8) -> Self {
         assert_unsafe_precondition!(
             check_language_ub,

library/core/src/char/convert.rs

@@ -21,7 +21,6 @@ pub(super) const fn from_u32(i: u32) -> Option<char> {
 /// Converts a `u32` to a `char`, ignoring validity. See [`char::from_u32_unchecked`].
 #[inline]
 #[must_use]
-#[track_caller]
 pub(super) const unsafe fn from_u32_unchecked(i: u32) -> char {
     // SAFETY: the caller must guarantee that `i` is a valid char value.
     unsafe {

library/core/src/hint.rs

@@ -97,7 +97,7 @@ use crate::{intrinsics, ub_checks};
 #[inline]
 #[stable(feature = "unreachable", since = "1.27.0")]
 #[rustc_const_stable(feature = "const_unreachable_unchecked", since = "1.57.0")]
-#[track_caller]
+#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 pub const unsafe fn unreachable_unchecked() -> ! {
     ub_checks::assert_unsafe_precondition!(
         check_language_ub,

library/core/src/intrinsics.rs

@@ -3295,7 +3295,7 @@ pub const fn ptr_metadata<P: ptr::Pointee<Metadata = M> + ?Sized, M>(_ptr: *cons
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")]
 #[inline(always)]
-#[track_caller]
+#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 #[rustc_diagnostic_item = "ptr_copy_nonoverlapping"]
 pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize) {
     extern "rust-intrinsic" {
@@ -3397,7 +3397,7 @@ pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: us
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")]
 #[inline(always)]
-#[track_caller]
+#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 #[rustc_diagnostic_item = "ptr_copy"]
 pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
     extern "rust-intrinsic" {
@@ -3477,7 +3477,7 @@ pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")]
 #[inline(always)]
-#[track_caller]
+#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
 #[rustc_diagnostic_item = "ptr_write_bytes"]
 pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
     extern "rust-intrinsic" {

library/core/src/num/int_macros.rs

@@ -510,7 +510,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -662,7 +662,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -814,7 +814,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1163,7 +1163,7 @@ macro_rules! int_impl {
                       without modifying the original"]
         #[rustc_const_unstable(feature = "unchecked_neg", issue = "85122")]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_neg(self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1296,7 +1296,7 @@ macro_rules! int_impl {
                       without modifying the original"]
         #[rustc_const_unstable(feature = "unchecked_shifts", issue = "85122")]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1422,7 +1422,7 @@ macro_rules! int_impl {
                       without modifying the original"]
         #[rustc_const_unstable(feature = "unchecked_shifts", issue = "85122")]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,

library/core/src/num/nonzero.rs

@@ -364,7 +364,6 @@ where
     #[rustc_const_stable(feature = "nonzero", since = "1.28.0")]
     #[must_use]
     #[inline]
-    #[track_caller]
     pub const unsafe fn new_unchecked(n: T) -> Self {
         match Self::new(n) {
             Some(n) => n,
@@ -405,7 +404,6 @@ where
     #[unstable(feature = "nonzero_from_mut", issue = "106290")]
     #[must_use]
     #[inline]
-    #[track_caller]
     pub unsafe fn from_mut_unchecked(n: &mut T) -> &mut Self {
         match Self::from_mut(n) {
             Some(n) => n,

library/core/src/num/uint_macros.rs

@@ -557,7 +557,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -749,7 +749,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -906,7 +906,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1485,7 +1485,7 @@ macro_rules! uint_impl {
                       without modifying the original"]
         #[rustc_const_unstable(feature = "unchecked_shifts", issue = "85122")]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1611,7 +1611,7 @@ macro_rules! uint_impl {
                       without modifying the original"]
         #[rustc_const_unstable(feature = "unchecked_shifts", issue = "85122")]
         #[inline(always)]
-        #[track_caller]
+        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
         pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,

library/core/src/ops/index_range.rs

@@ -18,7 +18,6 @@ impl IndexRange {
     /// # Safety
     /// - `start <= end`
     #[inline]
-    #[track_caller]
     pub const unsafe fn new_unchecked(start: usize, end: usize) -> Self {
         ub_checks::assert_unsafe_precondition!(
             check_library_ub,

library/core/src/panicking.rs

@@ -223,7 +223,6 @@ pub const fn panic_nounwind(expr: &'static str) -> ! {
 }
 
 /// Like `panic_nounwind`, but also inhibits showing a backtrace.
-#[track_caller]
 #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
 #[cfg_attr(feature = "panic_immediate_abort", inline)]
 #[rustc_nounwind]