Miri: use more specialized Scalar::from_ constructors where appropriate #70508
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
r? @varkor (rust_highfive has picked a reviewer for you, use r? to override) |
rust-highfive
added
the
S-waiting-on-review
RalfJung
changed the title
RalfJung
commented
Mar 28, 2020
| @@ -220,7 +222,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { | |||
| sym::discriminant_value => { | |||
| let place = self.deref_operand(args[0])?; | |||
| let discr_val = self.read_discriminant(place.into())?.0; | |||
| self.write_scalar(Scalar::from_uint(discr_val, dest.layout.size), dest)?; | |||
| self.write_scalar(Scalar::from_u64(u64::try_from(discr_val).unwrap()), dest)?; | |||
There was a problem hiding this comment.
@eddyb this is where Miri would now ICE for too big discriminants. (And I am not entirely sure what happens for negative discriminants, TBH...)
There was a problem hiding this comment.
Looking at this, I think for signed 64bit discriminants we appropriately truncate and everything is okay. (I tried to find a way to share that code there with cast.rs but found no good way.)
For negative discriminants with repr(i128) this will ICE, but well, these just cannot be represented properly in a u64...
|
r? @eddyb |
eddyb
approved these changes
Mar 28, 2020
|
@bors r+ |
|
📌 Commit bd9e046 has been approved by |
bors
added
S-waiting-on-bors
bors
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Mar 29, 2020
Rollup of 5 pull requests Successful merges: - rust-lang#69937 (ASCII methods on OsStr) - rust-lang#70235 (Validate git setup before accessing functionality) - rust-lang#70503 (rename Scalar::{ptr_null -> null_ptr} and add "machine_" prefix like elsewhere) - rust-lang#70508 (Miri: use more specialized Scalar::from_ constructors where appropriate) - rust-lang#70510 (fix TryEnterCriticalSection return type) Failed merges: r? @ghost
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
No description provided.