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