nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2025-05-14 02:49:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add a comment explaining the two checks

Browse Source
This commit is contained in:
Oliver S̶c̶h̶n̶e̶i̶d̶e̶r Scherer 2018-10-29 21:31:22 +01:00 committed by GitHub
parent 3ad154f484
commit 3e9d7e8aa8
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/librustc_mir/interpret/validity.rs
View File

@ -303,6 +303,7 @@ impl<'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> EvalContext<'a, 'mir, 'tcx, M>
let (lo, hi) = layout.valid_range.clone().into_inner();
let max_hi = u128::max_value() >> (128 - size.bits()); // as big as the size fits
assert!(hi <= max_hi);
// We could also write `(hi + 1) % (max_hi + 1) == lo` but `max_hi + 1` overflows for `u128`
if (lo == 0 && hi == max_hi) || (hi + 1 == lo) {
// Nothing to check
return Ok(());