diff options
| -rw-r--r-- | library/alloc/tests/slice.rs | 4 | ||||
| -rw-r--r-- | library/core/src/slice/mod.rs | 17 |
2 files changed, 18 insertions, 3 deletions
diff --git a/library/alloc/tests/slice.rs b/library/alloc/tests/slice.rs index 147f7f7d0c7..3c7d57f8b32 100644 --- a/library/alloc/tests/slice.rs +++ b/library/alloc/tests/slice.rs @@ -1522,7 +1522,7 @@ fn test_copy_from_slice() { } #[test] -#[should_panic(expected = "destination and source slices have different lengths")] +#[should_panic(expected = "source slice length (4) does not match destination slice length (5)")] fn test_copy_from_slice_dst_longer() { let src = [0, 1, 2, 3]; let mut dst = [0; 5]; @@ -1530,7 +1530,7 @@ fn test_copy_from_slice_dst_longer() { } #[test] -#[should_panic(expected = "destination and source slices have different lengths")] +#[should_panic(expected = "source slice length (4) does not match destination slice length (3)")] fn test_copy_from_slice_dst_shorter() { let src = [0, 1, 2, 3]; let mut dst = [0; 3]; diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs index f511ca8eb78..f2477ed6a6e 100644 --- a/library/core/src/slice/mod.rs +++ b/library/core/src/slice/mod.rs @@ -2501,7 +2501,22 @@ impl<T> [T] { where T: Copy, { - assert_eq!(self.len(), src.len(), "destination and source slices have different lengths"); + // The panic code path was put into a cold function to not bloat the + // call site. + #[inline(never)] + #[cold] + #[track_caller] + fn len_mismatch_fail(dst_len: usize, src_len: usize) -> ! { + panic!( + "source slice length ({}) does not match destination slice length ({})", + src_len, dst_len, + ); + } + + if self.len() != src.len() { + len_mismatch_fail(self.len(), src.len()); + } + // SAFETY: `self` is valid for `self.len()` elements by definition, and `src` was // checked to have the same length. The slices cannot overlap because // mutable references are exclusive. |