mirror
/
rustc-dev-guide
mirror of https://github.com/rust-lang/rustc-dev-guide.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

minor improvements

This commit is contained in:
Mark Mansi 2018-11-08 20:29:45 -06:00
parent c31a7a8076
commit 55f8aae0e1
1 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
src/borrow_check.md
View File

@ -51,13 +51,14 @@ the [`mir_borrowck`] query.
the purpose of this type check is to determine all of the constraints between the purpose of this type check is to determine all of the constraints between
different regions. different regions.
- Next, we do [region inference](borrow_check/region_inference.html), which computes - Next, we do [region inference](borrow_check/region_inference.html), which computes
the values of each region — basically, points in the control-flow graph. the values of each region — basically, the points in the control-flow graph where
each lifetime must be valid according to the constraints we collected.
- At this point, we can compute the "borrows in scope" at each point. - At this point, we can compute the "borrows in scope" at each point.
- Finally, we do a second walk over the MIR, looking at the actions it - Finally, we do a second walk over the MIR, looking at the actions it
does and reporting errors. For example, if we see a statement like does and reporting errors. For example, if we see a statement like
`*a + 1`, then we would check that the variable `a` is initialized `*a + 1`, then we would check that the variable `a` is initialized
and that it is not mutably borrowed, as either of those would and that it is not mutably borrowed, as either of those would
require an error to be reported. require an error to be reported. Doing this check requires the results of all
- Doing this check requires the results of all the previous analyses. the previous analyses.
[`replace_regions_in_mir`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_mir/borrow_check/nll/fn.replace_regions_in_mir.html [`replace_regions_in_mir`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_mir/borrow_check/nll/fn.replace_regions_in_mir.html