diff --git a/src/test/ui/consts/offset.rs b/src/test/ui/consts/offset.rs new file mode 100644 index 00000000000..f64242d568e --- /dev/null +++ b/src/test/ui/consts/offset.rs @@ -0,0 +1,115 @@ +// run-pass +#![feature(const_ptr_offset)] +#![feature(const_ptr_offset_from)] +#![feature(ptr_offset_from)] +use std::ptr; + +#[repr(C)] +struct Struct { + a: u32, + b: u32, + c: u32, +} +static S: Struct = Struct { a: 0, b: 0, c: 0 }; + +// For these tests we use offset_from to check that two pointers are equal. +// Rust doesn't currently support comparing pointers in const fn. + +static OFFSET_NO_CHANGE: bool = unsafe { + let p1 = &S.b as *const u32; + let p2 = p1.offset(2).offset(-2); + p1.offset_from(p2) == 0 +}; +static OFFSET_MIDDLE: bool = unsafe { + let p1 = (&S.a as *const u32).offset(1); + let p2 = (&S.c as *const u32).offset(-1); + p1.offset_from(p2) == 0 +}; +// Pointing to the end of the allocation is OK +static OFFSET_END: bool = unsafe { + let p1 = (&S.a as *const u32).offset(3); + let p2 = (&S.c as *const u32).offset(1); + p1.offset_from(p2) == 0 +}; +// Casting though a differently sized type is OK +static OFFSET_U8_PTR: bool = unsafe { + let p1 = (&S.a as *const u32 as *const u8).offset(5); + let p2 = (&S.c as *const u32 as *const u8).offset(-3); + p1.offset_from(p2) == 0 +}; +// Any offset with a ZST does nothing +const OFFSET_ZST: bool = unsafe { + let pz = &() as *const (); + // offset_from can't work with ZSTs, so cast to u8 ptr + let p1 = pz.offset(5) as *const u8; + let p2 = pz.offset(isize::MIN) as *const u8; + p1.offset_from(p2) == 0 +}; +const OFFSET_ZERO: bool = unsafe { + let p = [0u8; 0].as_ptr(); + p.offset(0).offset_from(p) == 0 +}; +const OFFSET_ONE: bool = unsafe { + let p = &42u32 as *const u32; + p.offset(1).offset_from(p) == 1 +}; +const OFFSET_DANGLING: bool = unsafe { + let p = ptr::NonNull::::dangling().as_ptr(); + p.offset(0).offset_from(p) == 0 +}; +const OFFSET_UNALIGNED: bool = unsafe { + let arr = [0u8; 32]; + let p1 = arr.as_ptr(); + let p2 = (p1.offset(2) as *const u32).offset(1); + (p2 as *const u8).offset_from(p1) == 6 +}; + +const WRAP_OFFSET_NO_CHANGE: bool = unsafe { + let p1 = &42u32 as *const u32; + let p2 = p1.wrapping_offset(1000).wrapping_offset(-1000); + let p3 = p1.wrapping_offset(-1000).wrapping_offset(1000); + (p1.offset_from(p2) == 0) & (p1.offset_from(p3) == 0) +}; +const WRAP_ADDRESS_SPACE: bool = unsafe { + let p1 = &42u8 as *const u8; + let p2 = p1.wrapping_offset(isize::MIN).wrapping_offset(isize::MIN); + p1.offset_from(p2) == 0 +}; +// Wrap on the count*size_of::() calculation. +const WRAP_SIZE_OF: bool = unsafe { + // Make sure that if p1 moves backwards, we are still in range + let arr = [0u32; 2]; + let p = &arr[1] as *const u32; + // With wrapping arithmetic, isize::MAX * 4 == -4 + let wrapped = p.wrapping_offset(isize::MAX); + let backward = p.wrapping_offset(-1); + wrapped.offset_from(backward) == 0 +}; +const WRAP_INTEGER_POINTER: bool = unsafe { + let p1 = (0x42 as *const u32).wrapping_offset(4); + let p2 = 0x52 as *const u32; + p1.offset_from(p2) == 0 +}; +const WRAP_NULL: bool = unsafe { + let p1 = ptr::null::().wrapping_offset(1); + let p2 = 0x4 as *const u32; + p1.offset_from(p2) == 0 +}; + +fn main() { + assert!(OFFSET_NO_CHANGE); + assert!(OFFSET_MIDDLE); + assert!(OFFSET_END); + assert!(OFFSET_U8_PTR); + assert!(OFFSET_ZST); + assert!(OFFSET_ZERO); + assert!(OFFSET_ONE); + assert!(OFFSET_DANGLING); + assert!(OFFSET_UNALIGNED); + + assert!(WRAP_OFFSET_NO_CHANGE); + assert!(WRAP_ADDRESS_SPACE); + assert!(WRAP_SIZE_OF); + assert!(WRAP_INTEGER_POINTER); + assert!(WRAP_NULL); +} diff --git a/src/test/ui/consts/offset_ub.rs b/src/test/ui/consts/offset_ub.rs new file mode 100644 index 00000000000..ac120789694 --- /dev/null +++ b/src/test/ui/consts/offset_ub.rs @@ -0,0 +1,22 @@ +// ignore-tidy-linelength +#![feature(const_ptr_offset)] +use std::ptr; + +// normalize-stderr-test "alloc\d+" -> "allocN" + +pub const BEFORE_START: *const u8 = unsafe { (&0u8 as *const u8).offset(-1) }; //~NOTE +pub const AFTER_END: *const u8 = unsafe { (&0u8 as *const u8).offset(2) }; //~NOTE +pub const AFTER_ARRAY: *const u8 = unsafe { [0u8; 100].as_ptr().offset(101) }; //~NOTE + +pub const OVERFLOW: *const u16 = unsafe { [0u16; 1].as_ptr().offset(isize::MAX) }; //~NOTE +pub const UNDERFLOW: *const u16 = unsafe { [0u16; 1].as_ptr().offset(isize::MIN) }; //~NOTE +pub const OVERFLOW_ADDRESS_SPACE: *const u8 = unsafe { (usize::MAX as *const u8).offset(2) }; //~NOTE +pub const UNDERFLOW_ADDRESS_SPACE: *const u8 = unsafe { (1 as *const u8).offset(-2) }; //~NOTE + +pub const ZERO_SIZED_ALLOC: *const u8 = unsafe { [0u8; 0].as_ptr().offset(1) }; //~NOTE +pub const DANGLING: *const u8 = unsafe { ptr::NonNull::::dangling().as_ptr().offset(4) }; //~NOTE + +// Right now, a zero offset from null is UB +pub const NULL_OFFSET_ZERO: *const u8 = unsafe { ptr::null::().offset(0) }; //~NOTE + +fn main() {} diff --git a/src/test/ui/consts/offset_ub.stderr b/src/test/ui/consts/offset_ub.stderr new file mode 100644 index 00000000000..b2b77586a50 --- /dev/null +++ b/src/test/ui/consts/offset_ub.stderr @@ -0,0 +1,154 @@ +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | overflowing in-bounds pointer arithmetic + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `BEFORE_START` at $DIR/offset_ub.rs:7:46 + | + ::: $DIR/offset_ub.rs:7:1 + | +LL | pub const BEFORE_START: *const u8 = unsafe { (&0u8 as *const u8).offset(-1) }; + | ------------------------------------------------------------------------------ + | + = note: `#[deny(const_err)]` on by default + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds test failed: pointer must be in-bounds at offset 2, but is outside bounds of allocN which has size 1 + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `AFTER_END` at $DIR/offset_ub.rs:8:43 + | + ::: $DIR/offset_ub.rs:8:1 + | +LL | pub const AFTER_END: *const u8 = unsafe { (&0u8 as *const u8).offset(2) }; + | -------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds test failed: pointer must be in-bounds at offset 101, but is outside bounds of allocN which has size 100 + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `AFTER_ARRAY` at $DIR/offset_ub.rs:9:45 + | + ::: $DIR/offset_ub.rs:9:1 + | +LL | pub const AFTER_ARRAY: *const u8 = unsafe { [0u8; 100].as_ptr().offset(101) }; + | ------------------------------------------------------------------------------ + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds pointer arithmetic: overflow computing offset + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `OVERFLOW` at $DIR/offset_ub.rs:11:43 + | + ::: $DIR/offset_ub.rs:11:1 + | +LL | pub const OVERFLOW: *const u16 = unsafe { [0u16; 1].as_ptr().offset(isize::MAX) }; + | ---------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds pointer arithmetic: overflow computing offset + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `UNDERFLOW` at $DIR/offset_ub.rs:12:44 + | + ::: $DIR/offset_ub.rs:12:1 + | +LL | pub const UNDERFLOW: *const u16 = unsafe { [0u16; 1].as_ptr().offset(isize::MIN) }; + | ----------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | overflowing in-bounds pointer arithmetic + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `OVERFLOW_ADDRESS_SPACE` at $DIR/offset_ub.rs:13:56 + | + ::: $DIR/offset_ub.rs:13:1 + | +LL | pub const OVERFLOW_ADDRESS_SPACE: *const u8 = unsafe { (usize::MAX as *const u8).offset(2) }; + | --------------------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | overflowing in-bounds pointer arithmetic + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `UNDERFLOW_ADDRESS_SPACE` at $DIR/offset_ub.rs:14:57 + | + ::: $DIR/offset_ub.rs:14:1 + | +LL | pub const UNDERFLOW_ADDRESS_SPACE: *const u8 = unsafe { (1 as *const u8).offset(-2) }; + | -------------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds test failed: pointer must be in-bounds at offset 1, but is outside bounds of allocN which has size 0 + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `ZERO_SIZED_ALLOC` at $DIR/offset_ub.rs:16:50 + | + ::: $DIR/offset_ub.rs:16:1 + | +LL | pub const ZERO_SIZED_ALLOC: *const u8 = unsafe { [0u8; 0].as_ptr().offset(1) }; + | ------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/mut_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) as *mut T + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | unable to turn bytes into a pointer + | inside `std::ptr::mut_ptr::::offset` at $SRC_DIR/libcore/ptr/mut_ptr.rs:LL:COL + | inside `DANGLING` at $DIR/offset_ub.rs:17:42 + | + ::: $DIR/offset_ub.rs:17:1 + | +LL | pub const DANGLING: *const u8 = unsafe { ptr::NonNull::::dangling().as_ptr().offset(4) }; + | --------------------------------------------------------------------------------------------- + +error: any use of this value will cause an error + --> $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | +LL | intrinsics::offset(self, count) + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | | + | inbounds test failed: 0x0 is not a valid pointer + | inside `std::ptr::const_ptr::::offset` at $SRC_DIR/libcore/ptr/const_ptr.rs:LL:COL + | inside `NULL_OFFSET_ZERO` at $DIR/offset_ub.rs:20:50 + | + ::: $DIR/offset_ub.rs:20:1 + | +LL | pub const NULL_OFFSET_ZERO: *const u8 = unsafe { ptr::null::().offset(0) }; + | ------------------------------------------------------------------------------- + +error: aborting due to 10 previous errors +