Feedback on LW1 EAR

[Tobias Hartmann]

Hi Uberto,

first of all, thanks a lot for trying out LW1 EA and for reporting these issues!

The crash is a bug in the just-in-time (JIT) compiler when compiling the WatchV:equals method, I've
filed [1] and will work on a fix.

As a temporary workaround you can disable JIT compilation of the affected method via
-XX:CompileCommand=exclude,"Knapsack\$WatchV::equals" or disable JIT compilation altogether by
adding the -Xint command line flag (unfortunately, both options will slow down execution a lot but
it should be good enough for non-performance testing).

Thanks,
Tobias

[1] https://bugs.openjdk.java.net/browse/JDK-8209687


On 18.08.2018 12:40, Uberto Barbini wrote:
> 5) I saw that I can override toString() and call super.toString() to have
> the standard Object behavior. I wonder if there will be some kind of base
> class for all ValueTypes or not.
> 
> 
> Then I've tried to replace some immutable classes into Value Types use them
> in my other projects.
> The main hindrance has been the missing support for generics.
> As workaround I've created a interface and based the collection on the
> interface. It worked in a few projects but I had a Fatal Error on a simple
> algorithm. I've tried to understand the exact problem but the same code
> seems to work as standalone project... If it's something worth
> investigating I can dig it more
> 
> https://github.com/uberto/eopi/blob/ValhallaLW01/src/test/java/com/gamasoft/eopi/cap17_DynamicProgramming/KnapsackTest.java
> 
> 
> #
> # A fatal error has been detected by the Java Runtime Environment:
> #
> #  SIGSEGV (0xb) at pc=0x00007f08c3d648aa, pid=18399, tid=18426
> #
> # JRE version: OpenJDK Runtime Environment (11.0) (build
> 11-lworldea+0-2018-07-30-1734349.david.simms.valhalla)
> # Java VM: OpenJDK 64-Bit Server VM
> (11-lworldea+0-2018-07-30-1734349.david.simms.valhalla, mixed mode,
> compressed oops, g1 gc, linux-amd64)
> # Problematic frame:
> # V  [libjvm.so+0x4148aa]  AddPNode::Value(PhaseGVN*) const+0x7a
> #
> # No core dump will be written. Core dumps have been disabled. To enable
> core dumping, try "ulimit -c unlimited" before starting Java again
> #
> # If you would like to submit a bug report, please visit:
> #   http://bugreport.java.com/bugreport/crash.jsp
> #