Improve safety & usability of |size_t| and |ssize_t|. #29222
Closed
Conversation
This file contains 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
|
Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @alexcrichton (or someone else) soon. If any changes to this PR are deemed necessary, please add them as extra commits. This ensures that the reviewer can see what has changed since they last reviewed the code. The way Github handles out-of-date commits, this should also make it reasonably obvious what issues have or haven't been addressed. Large or tricky changes may require several passes of review and changes. Please see the contribution instructions for more information. |
|
☔ The latest upstream changes (presumably #29045) made this pull request unmergeable. Please resolve the merge conflicts. |
Also, improve the documentation related to the range of usize and isize.
Since |usize| may be larger than |libc::size_t|, it is generally not safe to cast from |usize| to |libc::size_t|. The effect of this commit is to cause the build to fail on a platform where `libc::size_t` isn't the same as `usize`. But, that is better than the current state of affairs, where unsafe truncations can occur on such platforms, potentially leading to buffer overflows and other unsafety.
I didn't try to find every such cast. I concentrated on the files that had now-unnecessary casts from |usize| to |size_t|.
briansmith
force-pushed
the
size_t_ssize_t
branch
from
7a1906f
to
5864ba9
Compare
|
This is now against the wrong repo. |
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Outdated suggestions cannot be applied.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.
This has been rebased on top of #28779 and #29220. It is intended to address the
usize/isizerelated aspects of RFC 1291.Note in particular that one of these changesets removes casts that would actually result in unsafe memory usage on any platform where
libc::size_tis smaller thanusize.r? @alexcrichton