Return false from needs_drop for all zero-sized arrays.#65389
Merged
bors merged 3 commits intorust-lang:masterfrom Oct 16, 2019
Merged
Return false from needs_drop for all zero-sized arrays.#65389bors merged 3 commits intorust-lang:masterfrom
false from needs_drop for all zero-sized arrays.#65389bors merged 3 commits intorust-lang:masterfrom
Conversation
Contributor
|
r? @davidtwco (rust_highfive has picked a reviewer for you, use r? to override) |
rust-highfive
added
the
S-waiting-on-review
Contributor
Author
Member
|
r? @eddyb |
Contributor
|
We already special case zero sized arrays in other places so I'm comfortable with doing it here as well. However, cc @rust-lang/lang |
ecstatic-morse
force-pushed
the
zero-sized-array-no-drop
branch
from
82e9edc to
c08a871
Compare
Contributor
Author
|
I added a regression test for the underlying const validation issue as well. A perf run might be informative here. This will result in more calls to |
Contributor
|
@bors try @rust-timer queue |
Collaborator
|
Awaiting bors try build completion |
Collaborator
bors
added a commit
that referenced
this pull request
Oct 14, 2019
Return `false` from `needs_drop` for all zero-sized arrays. Resolves #65348. This changes the result of the `needs_drop` query from `true` to `false` for types such as `[Box<i32>; 0]`. I believe this change to be sound because a zero-sized array can never actually hold a value. This is an elegant way of resolving #65348 and #64945, but obviously it has much broader implications.
Collaborator
|
☀️ Try build successful - checks-azure |
Collaborator
|
Queued e823bc1 with parent 36d4506, future comparison URL. |
Collaborator
|
Finished benchmarking try commit e823bc1, comparison URL. |
Contributor
Author
|
Perf impact is negligible. Just needs an r+. |
Member
|
@bors r+ |
Collaborator
|
📌 Commit c08a871 has been approved by |
bors
added
S-waiting-on-bors
Centril
added a commit
to Centril/rust
that referenced
this pull request
Oct 15, 2019
…drop, r=eddyb Return `false` from `needs_drop` for all zero-sized arrays. Resolves rust-lang#65348. This changes the result of the `needs_drop` query from `true` to `false` for types such as `[Box<i32>; 0]`. I believe this change to be sound because a zero-sized array can never actually hold a value. This is an elegant way of resolving rust-lang#65348 and rust-lang#64945, but obviously it has much broader implications.
Centril
added a commit
to Centril/rust
that referenced
this pull request
Oct 15, 2019
…drop, r=eddyb Return `false` from `needs_drop` for all zero-sized arrays. Resolves rust-lang#65348. This changes the result of the `needs_drop` query from `true` to `false` for types such as `[Box<i32>; 0]`. I believe this change to be sound because a zero-sized array can never actually hold a value. This is an elegant way of resolving rust-lang#65348 and rust-lang#64945, but obviously it has much broader implications.
tmandry
added a commit
to tmandry/rust
that referenced
this pull request
Oct 15, 2019
…drop, r=eddyb Return `false` from `needs_drop` for all zero-sized arrays. Resolves rust-lang#65348. This changes the result of the `needs_drop` query from `true` to `false` for types such as `[Box<i32>; 0]`. I believe this change to be sound because a zero-sized array can never actually hold a value. This is an elegant way of resolving rust-lang#65348 and rust-lang#64945, but obviously it has much broader implications.
bors
added a commit
that referenced
this pull request
Oct 15, 2019
Rollup of 14 pull requests Successful merges: - #64603 (Reducing spurious unused lifetime warnings.) - #64623 (Remove last uses of gensyms) - #65235 (don't assume we can *always* find a return type hint in async fn) - #65242 (Fix suggestion to constrain trait for method to be found) - #65265 (Cleanup librustc mir err codes) - #65293 (Optimize `try_expand_impl_trait_type`) - #65307 (Try fix incorrect "explicit lifetime name needed") - #65308 (Add long error explanation for E0574) - #65353 (save-analysis: Don't ICE when resolving qualified type paths in struct members) - #65389 (Return `false` from `needs_drop` for all zero-sized arrays.) - #65402 (Add troubleshooting section to PGO chapter in rustc book.) - #65425 (Optimize `BitIter`) - #65438 (Organize `never_type` tests) - #65444 (Implement AsRef<[T]> for List<T>) Failed merges: - #65390 (Add long error explanation for E0576) r? @ghost
Collaborator
|
☔ The latest upstream changes (presumably #65454) made this pull request unmergeable. Please resolve the merge conflicts. |
bors
added
S-waiting-on-author
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
7 participants
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.
Resolves #65348.
This changes the result of the
needs_dropquery fromtruetofalsefor types such as[Box<i32>; 0]. I believe this change to be sound because a zero-sized array can never actually hold a value. This is an elegant way of resolving #65348 and #64945, but obviously it has much broader implications.