A different fix after https://github.com/openjdk/jdk/pull/14506 was closed.
Still haven't made the attributes set immutable but at least it is populated before an entry is added to `entries` and it will never be modified later. I tried the newly added `AttributesMultiThread.java` test hundreds of times and only observed failures before this fix (~%2 failure rate). ------------- Commit messages: - remove x bits - the fix Changes: https://git.openjdk.org/jdk/pull/15909/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=15909&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8309667 Stats: 258 lines in 3 files changed: 250 ins; 2 del; 6 mod Patch: https://git.openjdk.org/jdk/pull/15909.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/15909/head:pull/15909 PR: https://git.openjdk.org/jdk/pull/15909
