Determinism fix #1431
Merged
Determinism fix #1431
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
…pend on pointers. in remove-duplicate-functions, consider all comparisons in each hash group, not just the first in the group, as what groups we have can change between runs
jgravelle-google
approved these changes
Feb 16, 2018
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Outdated suggestions cannot be applied.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.
Hash results may differ between runs, as they can depend on pointers. In remove-duplicate-functions, that shouldn't matter, except that we only considered the first item in each hash group vs the others (to avoid
O(N^2)), which is fine except for hash collisions (collisions mean 2 groups are merged into one, and considering just the first item vs the rest we miss out on the other duplicates in that single group). And hash collisions do occur (rarely) in practice. Instead, consider all comparisons in each hash group, which should be fine unless we have large amounts of hash collisions.