Auto merge of rust-lang#129658 - saethlin:spare-a-crumb, r=<try>

Add some track_caller info to precondition panics

r? `@ghost`

Thought of this while looking at rust-lang#129642 (comment)

Author: bors

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -803,13 +803,15 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 let (fn_abi, llfn, instance) =
                     common::build_langcall(bx, Some(source_info.span), LangItem::PanicNounwind);
 
+                let location = self.get_caller_location(bx, source_info).immediate();
+
                 // Codegen the actual panic invoke/call.
                 helper.do_call(
                     self,
                     bx,
                     fn_abi,
                     llfn,
-                    &[msg.0, msg.1],
+                    &[msg.0, msg.1, location],
                     target.as_ref().map(|bb| (ReturnDest::Nothing, *bb)),
                     unwind,
                     &[],

compiler/rustc_codegen_ssa/src/size_of_val.rs

@@ -74,12 +74,20 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             // duplicated plenty of times.)
             let fn_ty = bx.fn_decl_backend_type(fn_abi);
 
+            let const_loc = bx.tcx().span_as_caller_location(rustc_span::DUMMY_SP);
+            let location = crate::mir::operand::OperandRef::from_const(
+                bx,
+                const_loc,
+                bx.tcx().caller_location_ty(),
+            )
+            .immediate();
+
             bx.call(
                 fn_ty,
                 /* fn_attrs */ None,
                 Some(fn_abi),
                 llfn,
-                &[msg.0, msg.1],
+                &[msg.0, msg.1, location],
                 None,
                 None,
             );

library/core/src/alloc/layout.rs

@@ -126,6 +126,7 @@ impl Layout {
     #[rustc_const_stable(feature = "const_alloc_layout_unchecked", since = "1.36.0")]
     #[must_use]
     #[inline]
+    #[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

@@ -503,6 +503,7 @@ 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

@@ -21,6 +21,7 @@ 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")]
-#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+#[track_caller]
 pub const unsafe fn unreachable_unchecked() -> ! {
     ub_checks::assert_unsafe_precondition!(
         check_language_ub,

library/core/src/intrinsics/mod.rs

@@ -4301,7 +4301,7 @@ pub const fn ptr_metadata<P: ptr::Pointee<Metadata = M> + ?Sized, M>(_ptr: *cons
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.83.0")]
 #[inline(always)]
-#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+#[track_caller]
 #[rustc_diagnostic_item = "ptr_copy_nonoverlapping"]
 pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize) {
     #[rustc_intrinsic_const_stable_indirect]
@@ -4407,7 +4407,7 @@ pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: us
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.83.0")]
 #[inline(always)]
-#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+#[track_caller]
 #[rustc_diagnostic_item = "ptr_copy"]
 pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
     #[rustc_intrinsic_const_stable_indirect]
@@ -4490,7 +4490,7 @@ pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
 #[rustc_allowed_through_unstable_modules]
 #[rustc_const_stable(feature = "const_ptr_write", since = "1.83.0")]
 #[inline(always)]
-#[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+#[track_caller]
 #[rustc_diagnostic_item = "ptr_write_bytes"]
 pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
     #[rustc_intrinsic_const_stable_indirect]

library/core/src/num/int_macros.rs

@@ -509,7 +509,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -659,7 +659,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -809,7 +809,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1153,7 +1153,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_neg(self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1281,7 +1281,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1402,7 +1402,7 @@ macro_rules! int_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,

library/core/src/num/nonzero.rs

@@ -394,6 +394,7 @@ 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,
@@ -434,6 +435,7 @@ 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

@@ -556,7 +556,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_add(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -746,7 +746,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -929,7 +929,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1499,7 +1499,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,
@@ -1620,7 +1620,7 @@ macro_rules! uint_impl {
         #[must_use = "this returns the result of the operation, \
                       without modifying the original"]
         #[inline(always)]
-        #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+        #[track_caller]
         pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self {
             assert_unsafe_precondition!(
                 check_language_ub,

library/core/src/ops/index_range.rs

@@ -18,6 +18,7 @@ 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

@@ -209,6 +209,7 @@ 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.
+#[track_caller]
 #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never), cold)]
 #[cfg_attr(feature = "panic_immediate_abort", inline)]
 #[lang = "panic_nounwind"] // needed by codegen for non-unwinding panics
@@ -219,6 +220,7 @@ 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]

library/core/src/ptr/alignment.rs

@@ -72,6 +72,7 @@ impl Alignment {
     /// It must *not* be zero.
     #[unstable(feature = "ptr_alignment_type", issue = "102070")]
     #[inline]
+    #[track_caller]
     pub const unsafe fn new_unchecked(align: usize) -> Self {
         assert_unsafe_precondition!(
             check_language_ub,

library/core/src/ptr/const_ptr.rs

@@ -399,7 +399,7 @@ impl<T: ?Sized> *const T {
     #[must_use = "returns a new pointer rather than modifying its argument"]
     #[rustc_const_stable(feature = "const_ptr_offset", since = "1.61.0")]
     #[inline(always)]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn offset(self, count: isize) -> *const T
     where
         T: Sized,
@@ -452,7 +452,7 @@ impl<T: ?Sized> *const T {
     #[inline(always)]
     #[stable(feature = "pointer_byte_offsets", since = "1.75.0")]
     #[rustc_const_stable(feature = "const_pointer_byte_offsets", since = "1.75.0")]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn byte_offset(self, count: isize) -> Self {
         // SAFETY: the caller must uphold the safety contract for `offset`.
         unsafe { self.cast::<u8>().offset(count).with_metadata_of(self) }
@@ -752,7 +752,7 @@ impl<T: ?Sized> *const T {
     #[unstable(feature = "ptr_sub_ptr", issue = "95892")]
     #[rustc_const_unstable(feature = "const_ptr_sub_ptr", issue = "95892")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn sub_ptr(self, origin: *const T) -> usize
     where
         T: Sized,
@@ -797,7 +797,7 @@ impl<T: ?Sized> *const T {
     #[unstable(feature = "ptr_sub_ptr", issue = "95892")]
     #[rustc_const_unstable(feature = "const_ptr_sub_ptr", issue = "95892")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn byte_sub_ptr<U: ?Sized>(self, origin: *const U) -> usize {
         // SAFETY: the caller must uphold the safety contract for `sub_ptr`.
         unsafe { self.cast::<u8>().sub_ptr(origin.cast::<u8>()) }
@@ -911,7 +911,7 @@ impl<T: ?Sized> *const T {
     #[must_use = "returns a new pointer rather than modifying its argument"]
     #[rustc_const_stable(feature = "const_ptr_offset", since = "1.61.0")]
     #[inline(always)]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn add(self, count: usize) -> Self
     where
         T: Sized,
@@ -963,7 +963,7 @@ impl<T: ?Sized> *const T {
     #[inline(always)]
     #[stable(feature = "pointer_byte_offsets", since = "1.75.0")]
     #[rustc_const_stable(feature = "const_pointer_byte_offsets", since = "1.75.0")]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn byte_add(self, count: usize) -> Self {
         // SAFETY: the caller must uphold the safety contract for `add`.
         unsafe { self.cast::<u8>().add(count).with_metadata_of(self) }
@@ -1017,7 +1017,7 @@ impl<T: ?Sized> *const T {
     #[must_use = "returns a new pointer rather than modifying its argument"]
     #[rustc_const_stable(feature = "const_ptr_offset", since = "1.61.0")]
     #[inline(always)]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn sub(self, count: usize) -> Self
     where
         T: Sized,
@@ -1075,7 +1075,7 @@ impl<T: ?Sized> *const T {
     #[inline(always)]
     #[stable(feature = "pointer_byte_offsets", since = "1.75.0")]
     #[rustc_const_stable(feature = "const_pointer_byte_offsets", since = "1.75.0")]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn byte_sub(self, count: usize) -> Self {
         // SAFETY: the caller must uphold the safety contract for `sub`.
         unsafe { self.cast::<u8>().sub(count).with_metadata_of(self) }
@@ -1246,7 +1246,7 @@ impl<T: ?Sized> *const T {
     #[stable(feature = "pointer_methods", since = "1.26.0")]
     #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn read(self) -> T
     where
         T: Sized,
@@ -1267,7 +1267,7 @@ impl<T: ?Sized> *const T {
     /// [`ptr::read_volatile`]: crate::ptr::read_volatile()
     #[stable(feature = "pointer_methods", since = "1.26.0")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub unsafe fn read_volatile(self) -> T
     where
         T: Sized,
@@ -1287,7 +1287,7 @@ impl<T: ?Sized> *const T {
     #[stable(feature = "pointer_methods", since = "1.26.0")]
     #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn read_unaligned(self) -> T
     where
         T: Sized,
@@ -1307,7 +1307,7 @@ impl<T: ?Sized> *const T {
     #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.83.0")]
     #[stable(feature = "pointer_methods", since = "1.26.0")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn copy_to(self, dest: *mut T, count: usize)
     where
         T: Sized,
@@ -1327,7 +1327,7 @@ impl<T: ?Sized> *const T {
     #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.83.0")]
     #[stable(feature = "pointer_methods", since = "1.26.0")]
     #[inline]
-    #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
+    #[track_caller]
     pub const unsafe fn copy_to_nonoverlapping(self, dest: *mut T, count: usize)
     where
         T: Sized,