Skip field retagging on ZSTs, it can take forever #2517
Merged
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
|
Makes sense! Seems we could optimize this a bit more and stop when the size is smaller than that of a pointer (and the type is not unsized)?
|
saethlin
force-pushed
the
zst-field-retagging
branch
from
f9b9e4d to
45bfd71
Compare
RalfJung
reviewed
Aug 29, 2022
RalfJung
reviewed
Aug 29, 2022
saethlin
force-pushed
the
zst-field-retagging
branch
from
45bfd71 to
70b960b
Compare
RalfJung
reviewed
Aug 29, 2022
|
Thanks. :) |
|
☀️ Test successful - checks-actions |
RalfJung
added a commit
to rust-lang/miri-test-libstd
that referenced
this pull request
Sep 2, 2022
This reverts commit 137592c. This times out; probably needs rust-lang/miri#2517
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Outdated suggestions cannot be applied.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.
I just tried running the
alloc's tests withmiri-test-libstdwith field retagging enabled. The test suite eventually hangs on a few tests which pass around ZSTs that have a lot of fields.I don't really know how to test this effectively. The test passes, but if you remove this fast-path it effectively just hangs the interpreter. And since it hangs inside a step, there's no hope for doing some kind of timeout within the test.