On Mon, 22 Mar 2021 19:40:19 GMT, Aleksei Voitylov <avoity...@openjdk.org>
wrote:
> With CDS and G1, test api/java_lang/ModuleLayer/Boot.html fails in JDK 16.
>
> After JDK-8253081 with CDS enabled two instances of empty layer appear in the
> runtime. One comes from default initialization of
> java/lang/ModuleLayer.EMPTY_LAYER, another one comes from CDS archive and is
> returned by ModuleLayer.boot().parents().get(0). The fix makes
> java/lang/ModuleLayer.EMPTY_LAYER a singleton with both CDS on and off,
> similar to java/lang/module/Configuration.EMPTY_CONFIGURATION.
>
> Testing: JCK 16, jtreg (including newly added test), pre-submit GitHub
> actions tests.
Marked as reviewed by alanb (Reviewer).
src/java.base/share/classes/java/lang/ModuleLayer.java line 156:
> 154:
> 155: static {
> 156: // Initialize EMPTY_LAYER from the archive.
Style wide you can drop L154 and L156 and the comment on EMPTY_LAYER will cover
its initialization too.
Otherwise looks okay but the more archiving we add does make it harder to
change this code.
-------------
PR: https://git.openjdk.java.net/jdk/pull/3131
