Enable permissive provenance by default
This completes the plan laid out in https://github.com/rust-lang/miri/issues/2133:
- We use permissive provenance with wildcard pointers by default.
- We print a warning on int2ptr casts. `-Zmiri-permissive-provenance` suppresses the warning; `-Zmiri-strict-provenance` turns it into a hard error.
- Raw pointer tagging is now always enabled, so we remove the `-Zmiri-tag-raw-pointers` flag and the code for untagged pointers. (Passing the flag still works, for compatibility -- but we just ignore it, with a warning.)
We also fix an intptrcast issue:
- Only live allocations are considered when computing the AllocId from an address.
So, finally, Miri has a good story for ptr2int2ptr roundtrips *and* no weird false negatives when doing raw pointer stuff with Stacked Borrows. :-) 🎉 Thanks a lot to everyone who helped with this, in particular `@carbotaniuman` who convinced me this is even possible.
Fixes https://github.com/rust-lang/miri/issues/2133
Fixes https://github.com/rust-lang/miri/issues/1866
Fixes https://github.com/rust-lang/miri/issues/1993
test that futexes induce appropriate synchronization
This fails when I remove the `validate_lock_acquire` or `validate_lock_release` from `futex_wake`. So finally we got those code paths actually covered in tests. :)
Format tests with rustfmt (288-299 of 299)
Extracted from #2097.
I'll make a separate PR to enable checking the `tests` directory's formatting in CI. I'll need to rebase that after both this and #2254 have landed, and if any new non-rustfmt-formatted files appear in the meantime, we can include formatting those in the same PR that enables the CI.
Format tests with rustfmt (225-275 of 300)
Extracted from #2097.
These cases all involve a line comment at the end of a block that rustfmt has chosen to wrap.
```diff
- unsafe { (*ptr).set(20); } //~ ERROR does not exist in the borrow stack
+ unsafe {
+ (*ptr).set(20);
+ } //~ ERROR does not exist in the borrow stack
```
I have moved all of those comments back onto the same line as the content of the block instead, as was indicated being `@RalfJung's` preference in https://github.com/rust-lang/miri/pull/2097#discussion_r862436672.
```diff
+ unsafe {
+ (*ptr).set(20); //~ ERROR does not exist in the borrow stack
+ }
```
