Assert in oopRecorder while compiling Graal

[Eric Caspole]

Hi everybody,
Since about last Thursday night my nightly Jenkins is getting new 
asserts like this:

#  Internal Error 
(/home/ecaspole/views/graal-default/graal/src/share/vm/code/oopRecorder.cpp:42), 
pid=21514, tid=140271113053952
#  assert(false) failed: duplicate found


This is happening in C2 while compiling Graal code itself, while running 
the HSAIL tests.

Usually:

Current CompileTask:
C2:  90345 17862       4 
com.oracle.graal.compiler.alloc.LinearScan::assignLocations (224 bytes)


Occasionally:

Current CompileTask:
C2:  91131 17255   !   4 
com.oracle.graal.compiler.gen.NodeLIRBuilder::doBlock (478 bytes)


This happens about half the time when I run the tests like below with 
debug or fastdebug build:

  ./mx.sh --vm server --vmbuild debug unittest -server -ea -esa 
-XX:-UseHSAILDeoptimization -XX:-UseCompressedOops  hsail.test

We haven't changed anything lately. Thanks for any advice.
Eric