diff --git a/library/core/src/ascii/ascii_char.rs b/library/core/src/ascii/ascii_char.rs
index ce09a0b444da3..48de4f17b1b3a 100644
--- a/library/core/src/ascii/ascii_char.rs
+++ b/library/core/src/ascii/ascii_char.rs
@@ -506,7 +506,7 @@ impl AsciiChar {
pub const unsafe fn digit_unchecked(d: u8) -> Self {
assert_unsafe_precondition!(
check_language_ub,
- "`AsciiChar::digit_unchecked` input cannot exceed 9.",
+ "`ascii::Char::digit_unchecked` input cannot exceed 9.",
(d: u8 = d) => d < 10
);
diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs
index d7a2f1909cabe..d76b7ca66cca4 100644
--- a/library/core/src/intrinsics.rs
+++ b/library/core/src/intrinsics.rs
@@ -64,6 +64,7 @@
#![allow(missing_docs)]
use crate::marker::{DiscriminantKind, Tuple};
+use crate::mem::SizedTypeProperties;
use crate::{ptr, ub_checks};
pub mod mir;
@@ -3311,10 +3312,12 @@ pub const unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: us
size: usize = size_of::<T>(),
align: usize = align_of::<T>(),
count: usize = count,
- ) =>
- ub_checks::is_aligned_and_not_null(src, align)
- && ub_checks::is_aligned_and_not_null(dst, align)
- && ub_checks::is_nonoverlapping(src, dst, size, count)
+ ) => {
+ let zero_size = count == 0 || size == 0;
+ ub_checks::is_aligned_and_not_null(src, align, zero_size)
+ && ub_checks::is_aligned_and_not_null(dst, align, zero_size)
+ && ub_checks::is_nonoverlapping(src, dst, size, count)
+ }
);
// SAFETY: the safety contract for `copy_nonoverlapping` must be
@@ -3412,9 +3415,10 @@ pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) {
src: *const () = src as *const (),
dst: *mut () = dst as *mut (),
align: usize = align_of::<T>(),
+ zero_size: bool = T::IS_ZST || count == 0,
) =>
- ub_checks::is_aligned_and_not_null(src, align)
- && ub_checks::is_aligned_and_not_null(dst, align)
+ ub_checks::is_aligned_and_not_null(src, align, zero_size)
+ && ub_checks::is_aligned_and_not_null(dst, align, zero_size)
);
copy(src, dst, count)
}
@@ -3491,7 +3495,8 @@ pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) {
(
addr: *const () = dst as *const (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ zero_size: bool = T::IS_ZST || count == 0,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, zero_size)
);
write_bytes(dst, val, count)
}
diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs
index 67f1b0cd16de4..62160937083c5 100644
--- a/library/core/src/ptr/mod.rs
+++ b/library/core/src/ptr/mod.rs
@@ -448,7 +448,7 @@
use crate::cmp::Ordering;
use crate::marker::FnPtr;
-use crate::mem::{self, MaybeUninit};
+use crate::mem::{self, MaybeUninit, SizedTypeProperties};
use crate::{fmt, hash, intrinsics, ub_checks};
mod alignment;
@@ -1165,10 +1165,12 @@ pub const unsafe fn swap_nonoverlapping<T>(x: *mut T, y: *mut T, count: usize) {
size: usize = size_of::<T>(),
align: usize = align_of::<T>(),
count: usize = count,
- ) =>
- ub_checks::is_aligned_and_not_null(x, align)
- && ub_checks::is_aligned_and_not_null(y, align)
- && ub_checks::is_nonoverlapping(x, y, size, count)
+ ) => {
+ let zero_size = size == 0 || count == 0;
+ ub_checks::is_aligned_and_not_null(x, align, zero_size)
+ && ub_checks::is_aligned_and_not_null(y, align, zero_size)
+ && ub_checks::is_nonoverlapping(x, y, size, count)
+ }
);
// Split up the slice into small power-of-two-sized chunks that LLVM is able
@@ -1277,7 +1279,8 @@ pub const unsafe fn replace<T>(dst: *mut T, src: T) -> T {
(
addr: *const () = dst as *const (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ is_zst: bool = T::IS_ZST,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, is_zst)
);
mem::replace(&mut *dst, src)
}
@@ -1429,7 +1432,8 @@ pub const unsafe fn read<T>(src: *const T) -> T {
(
addr: *const () = src as *const (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ is_zst: bool = T::IS_ZST,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, is_zst)
);
crate::intrinsics::read_via_copy(src)
}
@@ -1634,7 +1638,8 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) {
(
addr: *mut () = dst as *mut (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ is_zst: bool = T::IS_ZST,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, is_zst)
);
intrinsics::write_via_move(dst, src)
}
@@ -1806,7 +1811,8 @@ pub unsafe fn read_volatile<T>(src: *const T) -> T {
(
addr: *const () = src as *const (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ is_zst: bool = T::IS_ZST,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, is_zst)
);
intrinsics::volatile_load(src)
}
@@ -1885,7 +1891,8 @@ pub unsafe fn write_volatile<T>(dst: *mut T, src: T) {
(
addr: *mut () = dst as *mut (),
align: usize = align_of::<T>(),
- ) => ub_checks::is_aligned_and_not_null(addr, align)
+ is_zst: bool = T::IS_ZST,
+ ) => ub_checks::is_aligned_and_not_null(addr, align, is_zst)
);
intrinsics::volatile_store(dst, src);
}
diff --git a/library/core/src/slice/raw.rs b/library/core/src/slice/raw.rs
index 84e916b9a84e7..27bbadf7c89de 100644
--- a/library/core/src/slice/raw.rs
+++ b/library/core/src/slice/raw.rs
@@ -132,7 +132,7 @@ pub const unsafe fn from_raw_parts<'a, T>(data: *const T, len: usize) -> &'a [T]
align: usize = align_of::<T>(),
len: usize = len,
) =>
- ub_checks::is_aligned_and_not_null(data, align)
+ ub_checks::is_aligned_and_not_null(data, align, false)
&& ub_checks::is_valid_allocation_size(size, len)
);
&*ptr::slice_from_raw_parts(data, len)
@@ -187,7 +187,7 @@ pub const unsafe fn from_raw_parts_mut<'a, T>(data: *mut T, len: usize) -> &'a m
align: usize = align_of::<T>(),
len: usize = len,
) =>
- ub_checks::is_aligned_and_not_null(data, align)
+ ub_checks::is_aligned_and_not_null(data, align, false)
&& ub_checks::is_valid_allocation_size(size, len)
);
&mut *ptr::slice_from_raw_parts_mut(data, len)
diff --git a/library/core/src/ub_checks.rs b/library/core/src/ub_checks.rs
index c1a8c34539e6c..daaaf5a71953e 100644
--- a/library/core/src/ub_checks.rs
+++ b/library/core/src/ub_checks.rs
@@ -109,15 +109,15 @@ pub(crate) const fn check_language_ub() -> bool {
intrinsics::ub_checks() && const_eval_select((), comptime, runtime)
}
-/// Checks whether `ptr` is properly aligned with respect to
-/// `align_of::<T>()`.
+/// Checks whether `ptr` is properly aligned with respect to the given alignment, and
+/// if `is_zst == false`, that `ptr` is not null.
///
/// In `const` this is approximate and can fail spuriously. It is primarily intended
/// for `assert_unsafe_precondition!` with `check_language_ub`, in which case the
/// check is anyway not executed in `const`.
#[inline]
-pub(crate) const fn is_aligned_and_not_null(ptr: *const (), align: usize) -> bool {
- !ptr.is_null() && ptr.is_aligned_to(align)
+pub(crate) const fn is_aligned_and_not_null(ptr: *const (), align: usize, is_zst: bool) -> bool {
+ ptr.is_aligned_to(align) && (is_zst || !ptr.is_null())
}
#[inline]
diff --git a/tests/ui/precondition-checks/alignment.rs b/tests/ui/precondition-checks/alignment.rs
new file mode 100644
index 0000000000000..92400528fa07f
--- /dev/null
+++ b/tests/ui/precondition-checks/alignment.rs
@@ -0,0 +1,11 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: Alignment::new_unchecked requires
+
+#![feature(ptr_alignment_type)]
+
+fn main() {
+ unsafe {
+ std::ptr::Alignment::new_unchecked(0);
+ }
+}
diff --git a/tests/ui/precondition-checks/ascii-char-digit_unchecked.rs b/tests/ui/precondition-checks/ascii-char-digit_unchecked.rs
new file mode 100644
index 0000000000000..30c6f79fb08f0
--- /dev/null
+++ b/tests/ui/precondition-checks/ascii-char-digit_unchecked.rs
@@ -0,0 +1,11 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: `ascii::Char::digit_unchecked` input cannot exceed 9
+
+#![feature(ascii_char)]
+
+fn main() {
+ unsafe {
+ std::ascii::Char::digit_unchecked(b'a');
+ }
+}
diff --git a/tests/ui/precondition-checks/assert_unchecked.rs b/tests/ui/precondition-checks/assert_unchecked.rs
new file mode 100644
index 0000000000000..22b2b41455021
--- /dev/null
+++ b/tests/ui/precondition-checks/assert_unchecked.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: hint::assert_unchecked must never be called when the condition is false
+
+fn main() {
+ unsafe {
+ std::hint::assert_unchecked(false);
+ }
+}
diff --git a/tests/ui/precondition-checks/char-from_u32_unchecked.rs b/tests/ui/precondition-checks/char-from_u32_unchecked.rs
new file mode 100644
index 0000000000000..d950f20c77208
--- /dev/null
+++ b/tests/ui/precondition-checks/char-from_u32_unchecked.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: invalid value for `char`
+
+fn main() {
+ unsafe {
+ char::from_u32_unchecked(0xD801);
+ }
+}
diff --git a/tests/ui/precondition-checks/copy-nonoverlapping.rs b/tests/ui/precondition-checks/copy-nonoverlapping.rs
new file mode 100644
index 0000000000000..81018e4bff3e5
--- /dev/null
+++ b/tests/ui/precondition-checks/copy-nonoverlapping.rs
@@ -0,0 +1,25 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::copy_nonoverlapping requires
+//@ revisions: null_src null_dst misaligned_src misaligned_dst overlapping
+
+use std::ptr;
+
+fn main() {
+ let src = [0u16; 3];
+ let mut dst = [0u16; 3];
+ let src = src.as_ptr();
+ let dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null_src)]
+ ptr::copy_nonoverlapping(ptr::null(), dst, 1);
+ #[cfg(null_dst)]
+ ptr::copy_nonoverlapping(src, ptr::null_mut(), 1);
+ #[cfg(misaligned_src)]
+ ptr::copy_nonoverlapping(src.byte_add(1), dst, 1);
+ #[cfg(misaligned_dst)]
+ ptr::copy_nonoverlapping(src, dst.byte_add(1), 1);
+ #[cfg(overlapping)]
+ ptr::copy_nonoverlapping(dst, dst.add(1), 2);
+ }
+}
diff --git a/tests/ui/precondition-checks/copy.rs b/tests/ui/precondition-checks/copy.rs
new file mode 100644
index 0000000000000..694853f950ab5
--- /dev/null
+++ b/tests/ui/precondition-checks/copy.rs
@@ -0,0 +1,23 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::copy requires
+//@ revisions: null_src null_dst misaligned_src misaligned_dst
+
+use std::ptr;
+
+fn main() {
+ let src = [0u16; 3];
+ let mut dst = [0u16; 3];
+ let src = src.as_ptr();
+ let dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null_src)]
+ ptr::copy(ptr::null(), dst, 1);
+ #[cfg(null_dst)]
+ ptr::copy(src, ptr::null_mut(), 1);
+ #[cfg(misaligned_src)]
+ ptr::copy(src.byte_add(1), dst, 1);
+ #[cfg(misaligned_dst)]
+ ptr::copy(src, dst.byte_add(1), 1);
+ }
+}
diff --git a/tests/ui/precondition-checks/layout.rs b/tests/ui/precondition-checks/layout.rs
new file mode 100644
index 0000000000000..4fd1bbc4a994b
--- /dev/null
+++ b/tests/ui/precondition-checks/layout.rs
@@ -0,0 +1,15 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: Layout::from_size_align_unchecked requires
+//@ revisions: toolarge badalign
+//@[toolarge] compile-flags: --cfg toolarge
+//@[badalign] compile-flags: --cfg badalign
+
+fn main() {
+ unsafe {
+ #[cfg(toolarge)]
+ std::alloc::Layout::from_size_align_unchecked(isize::MAX as usize, 2);
+ #[cfg(badalign)]
+ std::alloc::Layout::from_size_align_unchecked(1, 3);
+ }
+}
diff --git a/tests/ui/precondition-checks/misaligned-slice.rs b/tests/ui/precondition-checks/misaligned-slice.rs
deleted file mode 100644
index 2963a0b5e6310..0000000000000
--- a/tests/ui/precondition-checks/misaligned-slice.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-//@ run-fail
-//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
-//@ error-pattern: unsafe precondition(s) violated: slice::from_raw_parts
-//@ ignore-debug
-
-fn main() {
- unsafe {
- let _s: &[u64] = std::slice::from_raw_parts(1usize as *const u64, 0);
- }
-}
diff --git a/tests/ui/precondition-checks/nonnull.rs b/tests/ui/precondition-checks/nonnull.rs
new file mode 100644
index 0000000000000..6b8edd4e5825e
--- /dev/null
+++ b/tests/ui/precondition-checks/nonnull.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: NonNull::new_unchecked requires
+
+fn main() {
+ unsafe {
+ std::ptr::NonNull::new_unchecked(std::ptr::null_mut::<u8>());
+ }
+}
diff --git a/tests/ui/precondition-checks/nonzero-from_mut_unchecked.rs b/tests/ui/precondition-checks/nonzero-from_mut_unchecked.rs
new file mode 100644
index 0000000000000..46ce7dc356fe2
--- /dev/null
+++ b/tests/ui/precondition-checks/nonzero-from_mut_unchecked.rs
@@ -0,0 +1,12 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: NonZero::from_mut_unchecked requires
+
+#![feature(nonzero_from_mut)]
+
+fn main() {
+ unsafe {
+ let mut num = 0u8;
+ std::num::NonZeroU8::from_mut_unchecked(&mut num);
+ }
+}
diff --git a/tests/ui/precondition-checks/nonzero-new_unchecked.rs b/tests/ui/precondition-checks/nonzero-new_unchecked.rs
new file mode 100644
index 0000000000000..7827a42844fd4
--- /dev/null
+++ b/tests/ui/precondition-checks/nonzero-new_unchecked.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: NonZero::new_unchecked requires
+
+fn main() {
+ unsafe {
+ std::num::NonZeroU8::new_unchecked(0);
+ }
+}
diff --git a/tests/ui/precondition-checks/null-slice.rs b/tests/ui/precondition-checks/null-slice.rs
deleted file mode 100644
index 280960358b7b3..0000000000000
--- a/tests/ui/precondition-checks/null-slice.rs
+++ /dev/null
@@ -1,10 +0,0 @@
-//@ run-fail
-//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
-//@ error-pattern: unsafe precondition(s) violated: slice::from_raw_parts
-//@ ignore-debug
-
-fn main() {
- unsafe {
- let _s: &[u8] = std::slice::from_raw_parts(std::ptr::null(), 0);
- }
-}
diff --git a/tests/ui/precondition-checks/out-of-bounds-get-unchecked.rs b/tests/ui/precondition-checks/out-of-bounds-get-unchecked.rs
deleted file mode 100644
index 011e92183fa47..0000000000000
--- a/tests/ui/precondition-checks/out-of-bounds-get-unchecked.rs
+++ /dev/null
@@ -1,11 +0,0 @@
-//@ run-fail
-//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
-//@ error-pattern: slice::get_unchecked requires
-//@ ignore-debug
-
-fn main() {
- unsafe {
- let sli: &[u8] = &[0];
- sli.get_unchecked(1);
- }
-}
diff --git a/tests/ui/precondition-checks/read.rs b/tests/ui/precondition-checks/read.rs
new file mode 100644
index 0000000000000..ab9921a0ceebe
--- /dev/null
+++ b/tests/ui/precondition-checks/read.rs
@@ -0,0 +1,18 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::read requires
+//@ revisions: null misaligned
+//@ ignore-test
+
+use std::ptr;
+
+fn main() {
+ let src = [0u16; 2];
+ let src = src.as_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::read(ptr::null::<u8>());
+ #[cfg(misaligned)]
+ ptr::read(src.byte_add(1));
+ }
+}
diff --git a/tests/ui/precondition-checks/read_volatile.rs b/tests/ui/precondition-checks/read_volatile.rs
new file mode 100644
index 0000000000000..e14881d029037
--- /dev/null
+++ b/tests/ui/precondition-checks/read_volatile.rs
@@ -0,0 +1,17 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::read_volatile requires
+//@ revisions: null misaligned
+
+use std::ptr;
+
+fn main() {
+ let src = [0u16; 2];
+ let src = src.as_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::read_volatile(ptr::null::<u8>());
+ #[cfg(misaligned)]
+ ptr::read_volatile(src.byte_add(1));
+ }
+}
diff --git a/tests/ui/precondition-checks/replace.rs b/tests/ui/precondition-checks/replace.rs
new file mode 100644
index 0000000000000..2808cee7b64b1
--- /dev/null
+++ b/tests/ui/precondition-checks/replace.rs
@@ -0,0 +1,17 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::replace requires
+//@ revisions: null misaligned
+
+use std::ptr;
+
+fn main() {
+ let mut dst = [0u16; 2];
+ let dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::replace(ptr::null_mut::<u8>(), 1);
+ #[cfg(misaligned)]
+ ptr::replace(dst.byte_add(1), 1u16);
+ }
+}
diff --git a/tests/ui/precondition-checks/slice-from-raw-parts-mut.rs b/tests/ui/precondition-checks/slice-from-raw-parts-mut.rs
new file mode 100644
index 0000000000000..3801639e2551b
--- /dev/null
+++ b/tests/ui/precondition-checks/slice-from-raw-parts-mut.rs
@@ -0,0 +1,16 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: slice::from_raw_parts_mut requires
+//@ revisions: null misaligned toolarge
+
+fn main() {
+ unsafe {
+ #[cfg(null)]
+ let _s: &mut [u8] = std::slice::from_raw_parts_mut(std::ptr::null_mut(), 0);
+ #[cfg(misaligned)]
+ let _s: &mut [u16] = std::slice::from_raw_parts_mut(1usize as *mut u16, 0);
+ #[cfg(toolarge)]
+ let _s: &mut [u16] =
+ std::slice::from_raw_parts_mut(2usize as *mut u16, isize::MAX as usize);
+ }
+}
diff --git a/tests/ui/precondition-checks/slice-from-raw-parts.rs b/tests/ui/precondition-checks/slice-from-raw-parts.rs
new file mode 100644
index 0000000000000..a3690fa045eb7
--- /dev/null
+++ b/tests/ui/precondition-checks/slice-from-raw-parts.rs
@@ -0,0 +1,15 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: slice::from_raw_parts requires
+//@ revisions: null misaligned toolarge
+
+fn main() {
+ unsafe {
+ #[cfg(null)]
+ let _s: &[u8] = std::slice::from_raw_parts(std::ptr::null(), 0);
+ #[cfg(misaligned)]
+ let _s: &[u16] = std::slice::from_raw_parts(1usize as *const u16, 0);
+ #[cfg(toolarge)]
+ let _s: &[u16] = std::slice::from_raw_parts(2usize as *const u16, isize::MAX as usize);
+ }
+}
diff --git a/tests/ui/precondition-checks/slice-get_unchecked.rs b/tests/ui/precondition-checks/slice-get_unchecked.rs
new file mode 100644
index 0000000000000..1d8188fb9531a
--- /dev/null
+++ b/tests/ui/precondition-checks/slice-get_unchecked.rs
@@ -0,0 +1,20 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: slice::get_unchecked requires
+//@ revisions: usize range range_to range_from backwards_range
+
+fn main() {
+ unsafe {
+ let s = &[0];
+ #[cfg(usize)]
+ s.get_unchecked(1);
+ #[cfg(range)]
+ s.get_unchecked(1..2);
+ #[cfg(range_to)]
+ s.get_unchecked(..2);
+ #[cfg(range_from)]
+ s.get_unchecked(2..);
+ #[cfg(backwards_range)]
+ s.get_unchecked(1..0);
+ }
+}
diff --git a/tests/ui/precondition-checks/slice-get_unchecked_mut.rs b/tests/ui/precondition-checks/slice-get_unchecked_mut.rs
new file mode 100644
index 0000000000000..34c1454af438d
--- /dev/null
+++ b/tests/ui/precondition-checks/slice-get_unchecked_mut.rs
@@ -0,0 +1,20 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: slice::get_unchecked_mut requires
+//@ revisions: usize range range_to range_from backwards_range
+
+fn main() {
+ unsafe {
+ let mut s = &mut [0];
+ #[cfg(usize)]
+ s.get_unchecked_mut(1);
+ #[cfg(range)]
+ s.get_unchecked_mut(1..2);
+ #[cfg(range_to)]
+ s.get_unchecked_mut(..2);
+ #[cfg(range_from)]
+ s.get_unchecked_mut(2..);
+ #[cfg(backwards_range)]
+ s.get_unchecked_mut(1..0);
+ }
+}
diff --git a/tests/ui/precondition-checks/slice-swap_unchecked.rs b/tests/ui/precondition-checks/slice-swap_unchecked.rs
new file mode 100644
index 0000000000000..227a49091ec22
--- /dev/null
+++ b/tests/ui/precondition-checks/slice-swap_unchecked.rs
@@ -0,0 +1,14 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: index out of bounds: the len is 2 but the index is 2
+//@ revisions: oob_a oob_b
+
+fn main() {
+ let mut pair = [0u8; 2];
+ unsafe {
+ #[cfg(oob_a)]
+ pair.swap(0, 2);
+ #[cfg(oob_b)]
+ pair.swap(2, 0);
+ }
+}
diff --git a/tests/ui/precondition-checks/str-get_unchecked.rs b/tests/ui/precondition-checks/str-get_unchecked.rs
new file mode 100644
index 0000000000000..14d17f997ec9b
--- /dev/null
+++ b/tests/ui/precondition-checks/str-get_unchecked.rs
@@ -0,0 +1,18 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: str::get_unchecked requires
+//@ revisions: range range_to range_from backwards_range
+
+fn main() {
+ unsafe {
+ let s = "💅";
+ #[cfg(range)]
+ s.get_unchecked(4..5);
+ #[cfg(range_to)]
+ s.get_unchecked(..5);
+ #[cfg(range_from)]
+ s.get_unchecked(5..);
+ #[cfg(backwards_range)]
+ s.get_unchecked(1..0);
+ }
+}
diff --git a/tests/ui/precondition-checks/str-get_unchecked_mut.rs b/tests/ui/precondition-checks/str-get_unchecked_mut.rs
new file mode 100644
index 0000000000000..ca1b169005559
--- /dev/null
+++ b/tests/ui/precondition-checks/str-get_unchecked_mut.rs
@@ -0,0 +1,19 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: str::get_unchecked_mut requires
+//@ revisions: range range_to range_from backwards_range
+
+fn main() {
+ unsafe {
+ let mut s: String = "💅".chars().collect();
+ let mut s: &mut str = &mut s;
+ #[cfg(range)]
+ s.get_unchecked_mut(4..5);
+ #[cfg(range_to)]
+ s.get_unchecked_mut(..5);
+ #[cfg(range_from)]
+ s.get_unchecked_mut(5..);
+ #[cfg(backwards_range)]
+ s.get_unchecked_mut(1..0);
+ }
+}
diff --git a/tests/ui/precondition-checks/swap-nonoverlapping.rs b/tests/ui/precondition-checks/swap-nonoverlapping.rs
new file mode 100644
index 0000000000000..52e4a3c870be5
--- /dev/null
+++ b/tests/ui/precondition-checks/swap-nonoverlapping.rs
@@ -0,0 +1,25 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::swap_nonoverlapping requires
+//@ revisions: null_src null_dst misaligned_src misaligned_dst overlapping
+
+use std::ptr;
+
+fn main() {
+ let mut src = [0u16; 3];
+ let mut dst = [0u16; 3];
+ let src = src.as_mut_ptr();
+ let dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null_src)]
+ ptr::swap_nonoverlapping(ptr::null_mut(), dst, 1);
+ #[cfg(null_dst)]
+ ptr::swap_nonoverlapping(src, ptr::null_mut(), 1);
+ #[cfg(misaligned_src)]
+ ptr::swap_nonoverlapping(src.byte_add(1), dst, 1);
+ #[cfg(misaligned_dst)]
+ ptr::swap_nonoverlapping(src, dst.byte_add(1), 1);
+ #[cfg(overlapping)]
+ ptr::swap_nonoverlapping(dst, dst.add(1), 2);
+ }
+}
diff --git a/tests/ui/precondition-checks/unchecked_add.rs b/tests/ui/precondition-checks/unchecked_add.rs
new file mode 100644
index 0000000000000..f44a6ea32ad8f
--- /dev/null
+++ b/tests/ui/precondition-checks/unchecked_add.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: u8::unchecked_add cannot overflow
+
+fn main() {
+ unsafe {
+ 1u8.unchecked_add(u8::MAX);
+ }
+}
diff --git a/tests/ui/precondition-checks/unchecked_mul.rs b/tests/ui/precondition-checks/unchecked_mul.rs
new file mode 100644
index 0000000000000..66655dda136e9
--- /dev/null
+++ b/tests/ui/precondition-checks/unchecked_mul.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: u8::unchecked_add cannot overflow
+
+fn main() {
+ unsafe {
+ 2u8.unchecked_add(u8::MAX);
+ }
+}
diff --git a/tests/ui/precondition-checks/unchecked_shl.rs b/tests/ui/precondition-checks/unchecked_shl.rs
new file mode 100644
index 0000000000000..1c96db0b1ec71
--- /dev/null
+++ b/tests/ui/precondition-checks/unchecked_shl.rs
@@ -0,0 +1,11 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: u8::unchecked_shl cannot overflow
+
+#![feature(unchecked_shifts)]
+
+fn main() {
+ unsafe {
+ 0u8.unchecked_shl(u8::BITS);
+ }
+}
diff --git a/tests/ui/precondition-checks/unchecked_shr.rs b/tests/ui/precondition-checks/unchecked_shr.rs
new file mode 100644
index 0000000000000..4a6d9ffb1d35b
--- /dev/null
+++ b/tests/ui/precondition-checks/unchecked_shr.rs
@@ -0,0 +1,11 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: u8::unchecked_shr cannot overflow
+
+#![feature(unchecked_shifts)]
+
+fn main() {
+ unsafe {
+ 0u8.unchecked_shr(u8::BITS);
+ }
+}
diff --git a/tests/ui/precondition-checks/unchecked_sub.rs b/tests/ui/precondition-checks/unchecked_sub.rs
new file mode 100644
index 0000000000000..545dde0e27809
--- /dev/null
+++ b/tests/ui/precondition-checks/unchecked_sub.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: u8::unchecked_sub cannot overflow
+
+fn main() {
+ unsafe {
+ 0u8.unchecked_sub(1u8);
+ }
+}
diff --git a/tests/ui/precondition-checks/unreachable_unchecked.rs b/tests/ui/precondition-checks/unreachable_unchecked.rs
new file mode 100644
index 0000000000000..2435450c4b5a1
--- /dev/null
+++ b/tests/ui/precondition-checks/unreachable_unchecked.rs
@@ -0,0 +1,9 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: hint::unreachable_unchecked must never be reached
+
+fn main() {
+ unsafe {
+ std::hint::unreachable_unchecked();
+ }
+}
diff --git a/tests/ui/precondition-checks/write.rs b/tests/ui/precondition-checks/write.rs
new file mode 100644
index 0000000000000..f76e776fcf35d
--- /dev/null
+++ b/tests/ui/precondition-checks/write.rs
@@ -0,0 +1,18 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::write requires
+//@ revisions: null misaligned
+//@ ignore-test
+
+use std::ptr;
+
+fn main() {
+ let mut dst = [0u16; 2];
+ let mut dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::write(ptr::null_mut::<u8>(), 1u8);
+ #[cfg(misaligned)]
+ ptr::write(dst.byte_add(1), 1u16);
+ }
+}
diff --git a/tests/ui/precondition-checks/write_bytes.rs b/tests/ui/precondition-checks/write_bytes.rs
new file mode 100644
index 0000000000000..3f64be9d1ee14
--- /dev/null
+++ b/tests/ui/precondition-checks/write_bytes.rs
@@ -0,0 +1,18 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::write requires
+//@ revisions: null misaligned
+//@ ignore-test
+
+use std::ptr;
+
+fn main() {
+ let mut dst = [0u16; 2];
+ let mut dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::write_bytes(ptr::null_mut::<u8>(), 1u8, 2);
+ #[cfg(misaligned)]
+ ptr::write_bytes(dst.byte_add(1), 1u8, 2);
+ }
+}
diff --git a/tests/ui/precondition-checks/write_volatile.rs b/tests/ui/precondition-checks/write_volatile.rs
new file mode 100644
index 0000000000000..ac0b89b5ecf2a
--- /dev/null
+++ b/tests/ui/precondition-checks/write_volatile.rs
@@ -0,0 +1,17 @@
+//@ run-fail
+//@ compile-flags: -Copt-level=3 -Cdebug-assertions=no -Zub-checks=yes
+//@ error-pattern: unsafe precondition(s) violated: ptr::write_volatile requires
+//@ revisions: null misaligned
+
+use std::ptr;
+
+fn main() {
+ let mut dst = [0u16; 2];
+ let mut dst = dst.as_mut_ptr();
+ unsafe {
+ #[cfg(null)]
+ ptr::write_volatile(ptr::null_mut::<u8>(), 1u8);
+ #[cfg(misaligned)]
+ ptr::write_volatile(dst.byte_add(1), 1u16);
+ }
+}
diff --git a/tests/ui/precondition-checks/zero-size-null.rs b/tests/ui/precondition-checks/zero-size-null.rs
new file mode 100644
index 0000000000000..43a81175f9448
--- /dev/null
+++ b/tests/ui/precondition-checks/zero-size-null.rs
@@ -0,0 +1,21 @@
+// Test that none of the precondition checks panic on zero-sized reads or writes through null.
+
+//@ run-pass
+//@ compile-flags: -Zmir-opt-level=0 -Copt-level=0 -Cdebug-assertions=yes
+
+use std::ptr;
+
+fn main() {
+ unsafe {
+ ptr::copy_nonoverlapping::<u8>(ptr::null(), ptr::null_mut(), 0);
+ ptr::copy_nonoverlapping::<()>(ptr::null(), ptr::null_mut(), 123);
+ ptr::copy::<u8>(ptr::null(), ptr::null_mut(), 0);
+ ptr::copy::<()>(ptr::null(), ptr::null_mut(), 123);
+ ptr::swap::<()>(ptr::null_mut(), ptr::null_mut());
+ ptr::replace::<()>(ptr::null_mut(), ());
+ ptr::read::<()>(ptr::null());
+ ptr::write::<()>(ptr::null_mut(), ());
+ ptr::read_volatile::<()>(ptr::null());
+ ptr::write_volatile::<()>(ptr::null_mut(), ());
+ }
+}