1 
 2 *** Project Valhalla "L-World Value Types" Early Access ***
 3 
 4 Prototype Version: LW2
 5 
 6 This is an "early access" build, from "Project Valhalla" [1], aimed at testing a
 7 "Value Types" implementation within the JVM, where-by value types may
 8 interoperate with existing type descriptors. Otherwise known as "L-World Value
 9 Types" (L-World) [2].
10 
11 Intended for a number of expert users with active interest in the
12 Valhalla project, and is provided as a convenience to users needing to build
13 from source code (branch "lworld") [3].
14 
15 Warning, not only is this build based on an incomplete version of "JDK 12",
16 there has been less than comprehensive testing carried out.
17 
18 * System Limitations
19 
20 - platforms: x64 Linux, x64 Mac OS X, Windows
21 - no support for atomic fields containing value types (work-in-progress for an
22   update)
23 - no AOT, CDS, redefineclasses
24 - -Xint and C2 only, no C1, no tiered-compilation
25 - interpreter is not optimized, focus is on JIT optimization
26 
27 * EA disclaimer
28 
29 - EA release functionality might not be released in a GA binary.  Any EA
30   functionality might be changed or removed
31 - EA builds do not imply that the feature is being considered to any scheduled
32   OpenJDK release
33 - The list of supported platforms at GA might be different than the platforms
34   supported during EA
35 - These binaries have not been tested to the same level to which Oracle would
36   test a GA binary.  It has been produced for gathering feedback.  Use for any
37   other purpose is at your own risk
38 - These binaries might be missing security vulnerabilities fixes available in GA
39   binaries or in other OpenJDK projects
40 - Oracle does not provide support for these binaries
41 
42 * Filing Bugs
43 
44 Send email to valhalla-dev@openjdk.java.net
45 
46 Current known issues [4]
47 
48 [1] https://wiki.openjdk.java.net/display/valhalla/Main
49 [2] https://wiki.openjdk.java.net/display/valhalla/L-World+Value+Types
50 [3] http://hg.openjdk.java.net/valhalla/valhalla/
51 [4] https://bugs.openjdk.java.net/issues/?filter=35615