Skip to content

Commit

Permalink
make another test more robust against random alignment
Browse files Browse the repository at this point in the history
  • Loading branch information
RalfJung committed Aug 17, 2020
1 parent db159b8 commit 4711df2
Show file tree
Hide file tree
Showing 4 changed files with 28 additions and 20 deletions.
10 changes: 6 additions & 4 deletions tests/compile-fail/unaligned_pointers/unaligned_ptr1.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2,8 +2,10 @@
// compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows

fn main() {
let x = [2u16, 3, 4]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const u32;
// This must fail because alignment is violated: the allocation's base is not sufficiently aligned.
let _x = unsafe { *x }; //~ ERROR memory with alignment 2, but alignment 4 is required
for _ in 0..10 { // Try many times as this might work by chance.
let x = [2u16, 3, 4]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const u32;
// This must fail because alignment is violated: the allocation's base is not sufficiently aligned.
let _x = unsafe { *x }; //~ ERROR memory with alignment 2, but alignment 4 is required
}
}
12 changes: 7 additions & 5 deletions tests/compile-fail/unaligned_pointers/unaligned_ptr2.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2,9 +2,11 @@
// compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows

fn main() {
let x = [2u32, 3]; // Make it big enough so we don't get an out-of-bounds error.
let x = (x.as_ptr() as *const u8).wrapping_offset(3) as *const u32;
// This must fail because alignment is violated: the offset is not sufficiently aligned.
// Also make the offset not a power of 2, that used to ICE.
let _x = unsafe { *x }; //~ ERROR memory with alignment 1, but alignment 4 is required
for _ in 0..10 { // Try many times as this might work by chance.
let x = [2u32, 3]; // Make it big enough so we don't get an out-of-bounds error.
let x = (x.as_ptr() as *const u8).wrapping_offset(3) as *const u32;
// This must fail because alignment is violated: the offset is not sufficiently aligned.
// Also make the offset not a power of 2, that used to ICE.
let _x = unsafe { *x }; //~ ERROR memory with alignment 1, but alignment 4 is required
}
}
14 changes: 8 additions & 6 deletions tests/compile-fail/unaligned_pointers/unaligned_ptr3.rs
Original file line number Diff line number Diff line change
Expand Up @@ -2,10 +2,12 @@
// compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows

fn main() {
let x = [2u16, 3, 4, 5]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const *const u8; // cast to ptr-to-ptr, so that we load a ptr
// This must fail because alignment is violated. Test specifically for loading pointers,
// which have special code in miri's memory.
let _x = unsafe { *x };
//~^ ERROR memory with alignment 2, but alignment
for _ in 0..10 { // Try many times as this might work by chance.
let x = [2u16, 3, 4, 5]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const *const u8; // cast to ptr-to-ptr, so that we load a ptr
// This must fail because alignment is violated. Test specifically for loading pointers,
// which have special code in miri's memory.
let _x = unsafe { *x };
//~^ ERROR but alignment
}
}
12 changes: 7 additions & 5 deletions tests/compile-fail/unaligned_pointers/unaligned_ptr_addr_of.rs
Original file line number Diff line number Diff line change
Expand Up @@ -4,9 +4,11 @@
use std::ptr;

fn main() {
let x = [2u16, 3, 4]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const u32;
// This must fail because alignment is violated: the allocation's base is not sufficiently aligned.
// The deref is UB even if we just put the result into a raw pointer.
let _x = unsafe { ptr::raw_const!(*x) }; //~ ERROR memory with alignment 2, but alignment 4 is required
for _ in 0..10 { // Try many times as this might work by chance.
let x = [2u16, 3, 4]; // Make it big enough so we don't get an out-of-bounds error.
let x = &x[0] as *const _ as *const u32;
// This must fail because alignment is violated: the allocation's base is not sufficiently aligned.
// The deref is UB even if we just put the result into a raw pointer.
let _x = unsafe { ptr::raw_const!(*x) }; //~ ERROR memory with alignment 2, but alignment 4 is required
}
}

0 comments on commit 4711df2

Please sign in to comment.