From c64b66446f976f4159bbd710266713c77aa0c403 Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Tue, 17 Sep 2024 19:22:47 +0200 Subject: [PATCH] ptr_offset_unsigned_overflow: extend test --- tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs | 7 ++++--- tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr | 4 ++-- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs b/tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs index a2739842bc..a0fa49d3d6 100644 --- a/tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs +++ b/tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs @@ -1,7 +1,8 @@ fn main() { let x = &[0i32; 2]; let x = x.as_ptr().wrapping_add(1); - // If the `!0` is interpreted as `isize`, it is just `-1` and hence harmless. - // However, this is unsigned arithmetic, so really this is `usize::MAX` and hence UB. - unsafe { x.byte_add(!0).read() }; //~ERROR: does not fit in an `isize` + // If `usize::MAX` is interpreted as `isize`, it is just `-1` and hence harmless. + let _ = unsafe { x.byte_offset(usize::MAX as isize) }; + // However, `byte_add` uses unsigned arithmetic, so really this is `usize::MAX` and hence UB. + let _ = unsafe { x.byte_add(usize::MAX) }; //~ERROR: does not fit in an `isize` } diff --git a/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr b/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr index a5f046ec40..e03bdfdb85 100644 --- a/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr +++ b/tests/fail/intrinsics/ptr_offset_unsigned_overflow.stderr @@ -1,8 +1,8 @@ error: Undefined Behavior: overflowing pointer arithmetic: the total offset in bytes does not fit in an `isize` --> tests/fail/intrinsics/ptr_offset_unsigned_overflow.rs:LL:CC | -LL | unsafe { x.byte_add(!0).read() }; - | ^^^^^^^^^^^^^^ overflowing pointer arithmetic: the total offset in bytes does not fit in an `isize` +LL | let _ = unsafe { x.byte_add(usize::MAX) }; + | ^^^^^^^^^^^^^^^^^^^^^^ overflowing pointer arithmetic: the total offset in bytes does not fit in an `isize` | = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information