value of forwarded variables stays the same. Has no effect if `-Zmiri-disable-isolation` is set.
* `-Zmiri-ignore-leaks` disables the memory leak checker, and also allows some
remaining threads to exist when the main thread exits.
+* `-Zmiri-num-cpus` states the number of available CPUs to be reported by miri. By default, the
+ number of available CPUs is `1`. Note that this flag does not affect how miri handles threads in
+ any way.
* `-Zmiri-permissive-provenance` disables the warning for integer-to-pointer casts and
[`ptr::from_exposed_addr`](https://doc.rust-lang.org/nightly/std/ptr/fn.from_exposed_addr.html).
This will necessarily miss some bugs as those operations are not efficiently and accurately
ensure alignment. (The standard library `align_to` method works fine in both modes; under
symbolic alignment it only fills the middle slice when the allocation guarantees sufficient
alignment.)
-* `-Zmiri-tag-gc=<blocks>` configures how often the pointer tag garbage collector runs. The default
- is to search for and remove unreachable tags once every `10,000` basic blocks. Setting this to
- `0` disables the garbage collector, which causes some programs to have explosive memory usage
- and/or super-linear runtime.
The remaining flags are for advanced use only, and more likely to change or be removed.
Some of these are **unsound**, which means they can lead
This is **work in progress**; currently, only integer arguments and return values are
supported (and no, pointer/integer casts to work around this limitation will not work;
they will fail horribly). It also only works on unix hosts for now.
- Follow [the discussion on supporting other types](https://github.com/rust-lang/miri/issues/2365).
+ Follow [the discussion on supporting other types](https://github.com/rust-lang/miri/issues/2365).
* `-Zmiri-measureme=<name>` enables `measureme` profiling for the interpreted program.
This can be used to find which parts of your program are executing slowly under Miri.
The profile is written out to a file with the prefix `<name>`, and can be processed
* `-Zmiri-retag-fields` changes Stacked Borrows retagging to recurse into fields.
This means that references in fields of structs/enums/tuples/arrays/... are retagged,
and in particular, they are protected when passed as function arguments.
+* `-Zmiri-tag-gc=<blocks>` configures how often the pointer tag garbage collector runs. The default
+ is to search for and remove unreachable tags once every `10000` basic blocks. Setting this to
+ `0` disables the garbage collector, which causes some programs to have explosive memory usage
+ and/or super-linear runtime.
* `-Zmiri-track-alloc-id=<id1>,<id2>,...` shows a backtrace when the given allocations are
being allocated or freed. This helps in debugging memory leaks and
use after free bugs. Specifying this argument multiple times does not overwrite the previous
Borrows "protectors". Specifying this argument multiple times does not overwrite the previous
values, instead it appends its values to the list. Listing an id multiple times has no effect.
* `-Zmiri-track-pointer-tag=<tag1>,<tag2>,...` shows a backtrace when a given pointer tag
- is created and when (if ever) it is popped from a borrow stack (which is where the tag becomes invalid
+ is created and when (if ever) it is popped from a borrow stack (which is where the tag becomes invalid
and any future use of it will error). This helps you in finding out why UB is
happening and where in your code would be a good place to look for it.
Specifying this argument multiple times does not overwrite the previous
some compiler flags to prepare the code for interpretation; with `host`, this is not done.
This environment variable is useful to be sure that the compiled `rlib`s are compatible
with Miri.
-* `MIRI_CALLED_FROM_XARGO` is set during the Miri-induced `xargo` sysroot build,
+* `MIRI_CALLED_FROM_SETUP` is set during the Miri sysroot build,
which will re-invoke `cargo-miri` as the `rustc` to use for this build.
* `MIRI_CALLED_FROM_RUSTDOC` when set to any value tells `cargo-miri` that it is
running as a child process of `rustdoc`, which invokes it twice for each doc-test
projects / rust.git / blobdiff