% java_g -XX:+VerifyBeforeGC <app-that-gc's at least once>

[Full GC [Tenured VerifyBeforeGC:[Verifying threads permgen tenured generation def new generation remset syms strs zone dict #
# HotSpot Virtual Machine Error, assertion failure
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Java VM: Java HotSpot(TM) Server VM (1.4.1-internal-debug mixed mode)
#
# assert(!h->gc_is_active(), "GC active during No_GC_Verifier")
#
# Error happened during: full generation collection
#
# Error ID: /net/spot/archive02/ysr/merge/src/share/vm/memory/gcLocker.cpp, 24 [ Patched ]
#
# Problematic Thread: prio=5 tid=0x3d700 nid=0x1 waiting on condition
#
assertion failure
assert(!h->gc_is_active(), "GC active during No_GC_Verifier")

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