On Fri, 12 Mar 2021 07:22:26 GMT, Aleksey Shipilev <sh...@openjdk.org> wrote:
>> SonarCloud reports multiple incorrect double-checked locking cases in >> `sun.java2d.CRenderer`. For example: >> >> >> Arc2D arcToShape; >> >> ... >> if (arcToShape == null) { >> synchronized (this) { >> if (arcToShape == null) { >> arcToShape = new Arc2D.Float(); >> } >> } >> } >> >> >> `Arc2D` contains fields that are not `final`. `arcToShape` is not >> `volatile`. This makes it an incorrect DCL. >> This code is used by Mac OS, do it would probably blow up some time later on >> M1. >> >> This is the candidate fix that preserves the semantics. I am doing this fix >> blindly so far, without testing on real Mac OS. But maybe there is no need >> to do any of this, because the setter methods overwrite the contents of all >> these objects under their own sync. So, maybe we can just allocate those >> objects without DCL-backed caching and pass them in? > > Aleksey Shipilev has updated the pull request incrementally with one > additional commit since the last revision: > > Drop DCL and useless synchronization completely LGTM ------------- Marked as reviewed by prr (Reviewer). PR: https://git.openjdk.java.net/jdk/pull/2948