The ModificationWatchpoints consistently crashes the Merlin VM with
a ShouldNotReachHere in InterpreterRuntime::post_field_modification
(tested on Solaris-sparc). Backtrace:

#
# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# ShouldNotReachHere()
#
# Error ID: /usr/re/hotspot/hotspot1.4/ws/solsparc/hotspot1.4beta/src/share/vm/interpreter/interpreterRuntime.cpp, 994 [ Patched ]
#
# Problematic Thread: prio=5 tid=0x3a7c0 nid=0x1 runnable
#
Dumping core....
t@1 (l@4) signal ABRT (Abort) in __sigprocmask at 0xff369968
0xff369968: __sigprocmask+0x0008: jmp %o7 + 0x8
Current function is main
  322 (*env)->CallStaticVoidMethod(env, mainClass, mainID, mainArgs);
(/java/devtools/sparc/SUNWspro/5.0/bin/../WS5.0/bin/sparcv9/dbx) where
current thread: t@1
  [1] __sigprocmask(0x0, 0xffbedb38, 0x0, 0xffffffff, 0xffffffff, 0x0), at 0xff369968
  [2] _resetsig(0xff37c524, 0x0, 0x25d38, 0x0, 0x0, 0x25db4), at 0xff35f1e8
  [3] _sigon(0xff380fc0, 0xff380fa0, 0x25dac, 0xffbedc0c, 0x6, 0x1), at 0xff35e934
  [4] _thrp_kill(0x0, 0x1, 0x6, 0xff37c524, 0x25d38, 0xff380924), at 0xff3617ac
  [5] abort(0xff332118, 0xffbedd08, 0x0, 0xfffffff8, 0x0, 0xffbedd29), at 0xff2b9338
  [6] os::abort(0x1, 0xfe1f9aec, 0xffbee5ac, 0x100, 0x145, 0x8), at 0xfdd006b8
  [7] report_error(0x1, 0xfe22341c, 0x3e2, 0xfe1f9984, 0xfe1f9994, 0x1), at 0xfd9f14b0
  [8] report_should_not_reach_here(0xfe22341c, 0x3e2, 0xb3, 0xffbee794, 0x3c, 0x145), at 0xfd9f0980
  [9] InterpreterRuntime::post_field_modification(0x3a7c0, 0x0, 0xf90dd6b8, 0xffbee84c, 0x0, 0x0), at 0xfdad6078
  [10] 0xfb422860(0x3a7c0, 0xb8, 0xffbee948, 0xfb421a00, 0x0, 0x0), at 0xfb42285f
  [11] 0xfb4064f4(0x3a7c0, 0xb8, 0x0, 0xfb424510, 0xf5200000, 0x0), at 0xfb4064f3
  [12] 0xfb4064f4(0xf5051d00, 0x3a7c0, 0x8, 0xfb421a00, 0xffbeec28, 0x29), at 0xfb4064f3
  [13] 0xfb400528(0xffbeea50, 0xffbeecf8, 0xa, 0xf90dd2c8, 0xfb40c420, 0xffbeec1c), at 0xfb400527
  [14] JavaCalls::call_helper(0xffbeec18, 0xfb4004a0, 0xffbeec10, 0x3a7c0, 0xff338aa0, 0xff3c0060), at 0xfdb11dd0
  [15] os::os_exception_wrapper(0xfdb117f0, 0xffbeecf0, 0xffbeebf8, 0xffbeec10, 0x3a7c0, 0xff0000), at 0xfdd0405c
  [16] JavaCalls::call(0xffbeecf0, 0xffbeebf8, 0xffbeec10, 0x3a7c0, 0xffbeec54, 0x1), at 0xfdb11780
  [17] jni_invoke(0x3a858, 0xffbeecf0, 0x0, 0x0, 0x120350, 0xffbeecd4), at 0xfdb35320
  [18] jni_CallStaticVoidMethod(0x3a858, 0x3b350, 0x120350, 0x3b358, 0xffbef5c0, 0x73657276), at 0xfdb4a0dc
=>[19] main(argc = 0, argv = 0xffbef65c), line 322 in "java.c"

/////////////////////////////////////////
al.smith@eng 2001-05-10

Regression test com/sun/jdi/ModificationWatchpoints.java fails with Merlin build 63 on Linux 6.2, host seahund. This test has not passed since it was introduced in b57.
For test hardware config's, see http://sqesvr.eng/st3/jdk1.4/docs/Merlin-hw.html
 
 #Test Results (version 2)
#Thu May 03 12:38:13 GMT+00:00 2001
#checksum:45e319aee2461229
#-----testdescription-----
$file=/.automount/sqesvr/root/export/st1/regression/merlin/jdk1.4Tests/tests/b63/com/sun/jdi/ModificationWatchpoints.java
$root=/.automount/sqesvr/root/export/st1/regression/merlin/jdk1.4Tests/tests/b63
author=Robert Field (modified to JDIScaffold)
keywords=bug4409582 othervm
library=scaffold
run=USER_SPECIFIED build JDIScaffold VMConnection\nUSER_SPECIFIED compile -g ModificationWatchpoints.java\nUSER_SPECIFIED
main/othervm ModificationWatchpoints\n
source=ModificationWatchpoints.java
title=Test all info returned by modification watchpoints

#-----environment-----

#-----testresult-----
description=file:///.automount/sqesvr/root/export/st1/regression/merlin/jdk1.4Tests/tests/b63/com/sun/jdi/ModificationWatchpoi
nts.java
end=Thu May 03 12:38:13 GMT+00:00 2001
environment=regtest
execStatus=Failed. Execution failed: `main' threw exception: com.sun.jdi.VMDisconnectedException
javatestOS=Linux 2.2.14-6.1.1 (i386)
javatestVersion=JT_2.1.3i
script=com.sun.javatest.regtest.RegressionScript
sections=script_messages build compile build main
start=Thu May 03 12:38:05 GMT+00:00 2001
status=Failed. Execution failed: `main' threw exception: com.sun.jdi.VMDisconnectedException
test=com/sun/jdi/ModificationWatchpoints.java
work=/export0/results/regression/merlin/b63/seahund.2.2.14-6.1.1-jth13-jdk14b63-05.03-09.14-ALL/com/sun/jdi

#section:script_messages
----------messages:(1/102)----------
JDK under test: java full version "1.4.0-beta-b63" (/net/sqesvr/export/st1/jdk14-beta/b63/linux-i386)

#section:build
----------messages:(3/127)----------
command: build VMConnection
reason: User specified action: run build JDIScaffold VMConnection
elapsed time (seconds): 0.0040
result: Passed. No need to compile: VMConnection.java

#section:compile
----------messages:(3/240)----------
command: compile
/.automount/sqesvr/root/export/st1/regression/merlin/jdk1.4Tests/tests/b63/com/sun/jdi/ModificationWatchpoints.java
reason: User specified action: run compile -g ModificationWatchpoints.java
elapsed time (seconds): 2.862
----------System.out:(0/0)----------
----------System.err:(0/0)----------
result: Passed. Compilation successful

#section:build
----------messages:(3/107)----------
command: build ModificationWatchpoints
reason: Named class compiled on demand
elapsed time (seconds): 0.0
result: Passed. No need to compile: ModificationWatchpoints.java

#section:main
----------messages:(3/141)----------
command: main ModificationWatchpoints
reason: User specified action: run main/othervm ModificationWatchpoints
elapsed time (seconds): 4.906
----------System.out:(34/1999)----------
run args: [ModificationWatchpointsTarg]
JVM version:1.4.0-beta
JDI version: 1.4
JVM description: Java Debug Interface (Reference Implementation) version 1.4
Java Debug Wire Protocol (Reference Implementation) version 1.4
JVM Debug Interface version 1.1
JVM version 1.4.0-beta (Java HotSpot(TM) Client VM, interpreted mode)
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iByte
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iChar
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iShort
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iInt
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iLong
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iFloat
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iDouble
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iString
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.iObject
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sByte
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sChar
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sShort
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sInt
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sLong
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sFloat
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sDouble
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sString
set watchpoint: ModificationWatchpointsTarg.ModificationWatchpointsTarg.sObject
#
# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Error ID: 494E54455250524554455232554E54494D450E4350500400
#
# Problematic Thread: prio=1 tid=0x0x8055480 nid=0x3a2a runnable
#
----------System.err:(18/992)----------
com.sun.jdi.VMDisconnectedException
at TestScaffold.waitForVMDeath(TestScaffold.java:298)
at TestScaffold.resumeToVMDeath(TestScaffold.java:468)
at TestScaffold.listenUntilVMDeath(TestScaffold.java:270)
at ModificationWatchpoints.runTests(ModificationWatchpoints.java:218)
at TestScaffold.startTests(TestScaffold.java:150)
at ModificationWatchpoints.main(ModificationWatchpoints.java:168)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:30)
at sun.reflect.InflatableMethodAccessorImpl.invoke(InflatableMethodAccessorImpl.java:48)
at java.lang.reflect.Method.invoke(Method.java:306)
at com.sun.javatest.regtest.MainWrapper$MainThread.run(MainWrapper.java:94)
at java.lang.Thread.run(Thread.java:579)

JavaTest Message: Test threw exception: com.sun.jdi.VMDisconnectedException
JavaTest Message: shutting down test

STATUS:Failed.`main' threw exception: com.sun.jdi.VMDisconnectedException
result: Failed. Execution failed: `main' threw exception: com.sun.jdi.VMDisconnectedException


test result: Failed. Execution failed: `main' threw exception: com.sun.jdi.VMDisconnectedException
======================================================================