Running the attached Tree test with the JDK1.2-"P" build produces this SEGV :

SIGSEGV 11* segmentation violation
    si_signo [11]: SIGSEGV 11* segmentation violation
    si_errno [0]: Error 0
    si_code [1]: SEGV_MAPERR [addr: 0x10]

        stackpointer=eab6ee98

Full thread dump Classic VM (JDK-1.2fcs-P, green threads):
    "Screen Updater" (TID:0xebc99ff8, sys_thread_t:0x479920, state:CW) prio=4
        at java.lang.Object.wait(Native Method)
        at java.lang.Object.wait(Compiled Code)
        at sun.awt.ScreenUpdater.nextEntry(Compiled Code)
        at sun.awt.ScreenUpdater.run(Compiled Code)
    "Thread-0" (TID:0xebc99d70, sys_thread_t:0x476578, state:CW) prio=1
        at java.lang.Thread.sleep(Native Method)
        at Tree.run(Compiled Code)
        at java.lang.Thread.run(Compiled Code)
    "AWT-Motif" (TID:0xebcb3a60, sys_thread_t:0x345b08, state:MW) prio=5
        at sun.awt.motif.MToolkit.run(Native Method)
        at java.lang.Thread.run(Compiled Code)
    "SunToolkit.PostEventQueue-0" (TID:0xebcb3ff0, sys_thread_t:0x325f98, state:CW) prio=5
        at java.lang.Object.wait(Native Method)
        at java.lang.Object.wait(Compiled Code)
        at sun.awt.PostEventQueue.run(Compiled Code)
    "AWT-EventQueue-0" (TID:0xebcb3fc0, sys_thread_t:0x2d9400, state:R) prio=6
        at sun.awt.font.NativeFontWrapper.drawStringIndexed(Native Method)
        at sun.java2d.loops.drawStringIndexed.DrawString(Compiled Code)
        at sun.java2d.loops.RasterOutputManager.drawString(Compiled Code)
        at sun.awt.image.BufferedImageGraphics2D.drawString(Compiled Code)
        at sun.java2d.pipe.ValidatePipe.drawString(Compiled Code)
        at sun.java2d.SunGraphics2D.drawString(Compiled Code)
        at Tree.tree(Compiled Code)
        at Tree.drawDemo(Compiled Code)
        at Tree.paint(Compiled Code)
        at javax.swing.JComponent.paintChildren(Compiled Code)
        at javax.swing.JComponent.paint(Compiled Code)
        at javax.swing.JComponent.paintChildren(Compiled Code)
        at javax.swing.JComponent.paint(Compiled Code)
        at javax.swing.JLayeredPane.paint(Compiled Code)
        at javax.swing.JComponent.paintChildren(Compiled Code)
        at javax.swing.JComponent.paint(Compiled Code)
        at java.awt.Container.paint(Compiled Code)
        at sun.awt.motif.MComponentPeer.handleEvent(Compiled Code)
        at java.awt.Component.dispatchEventImpl(Compiled Code)
        at java.awt.Container.dispatchEventImpl(Compiled Code)
        ... (more frames not shown)
    "Finalizer" (TID:0xebc98320, sys_thread_t:0x69358, state:CW) prio=8
        at java.lang.Object.wait(Native Method)
        at java.lang.ref.ReferenceQueue.remove(Compiled Code)
        at java.lang.ref.ReferenceQueue.remove(Compiled Code)
        at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:174)
    "Reference Handler" (TID:0xebc983b0, sys_thread_t:0x64ea8, state:CW) prio=10
        at java.lang.Object.wait(Native Method)
        at java.lang.Object.wait(Compiled Code)
        at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:114)
    "Signal dispatcher" (TID:0xebc983e0, sys_thread_t:0x5e128, state:CW) prio=5
    "Thread-1" (TID:0xebc9a608, sys_thread_t:0x26a30, state:CW) prio=5
Monitor Cache Dump:
    java.lang.Class@EBCA4780/EBD07DF8: owner "AWT-EventQueue-0" (0x2d9400) 2 entries
        Waiting to enter:
            "AWT-Motif" (0x345b08)
    sun.awt.PostEventQueue@EBCB3FF0/EBCFA0B8: <unowned>
        Waiting to be notified:
            "SunToolkit.PostEventQueue-0" (0x325f98)
    java.lang.ref.ReferenceQueue$Lock@EBC98338/EBCCDD68: <unowned>
        Waiting to be notified:
            "Finalizer" (0x69358)
    sun.awt.ScreenUpdater@EBC99FF8/EBD95FF8: <unowned>
        Waiting to be notified:
            "Screen Updater" (0x479920)
    java.awt.Component$AWTTreeLock@EBC9C5A0/EBCFA0B0: owner "AWT-EventQueue-0" (0x2d9400) 3 entries
    java.lang.ref.Reference$Lock@EBC983C0/EBCCD8A8: <unowned>
        Waiting to be notified:
            "Reference Handler" (0x64ea8)
Registered Monitor Dump:
    PCMap lock: <unowned>
    utf8 hash table: <unowned>
    JNI pinning lock: <unowned>
    JNI global reference lock: <unowned>
    BinClass lock: <unowned>
    Class linking lock: <unowned>
    System class loader lock: <unowned>
    Code rewrite lock: <unowned>
    Heap lock: <unowned>
    Monitor cache lock: owner "AWT-EventQueue-0" (0x2d9400) 1 entry
    Dynamic loading lock: <unowned>
    Monitor IO lock: <unowned>
    User signal monitor: <unowned>
        Waiting to be notified:
            "Signal dispatcher" (0x5e128)
    Child death monitor: <unowned>
    I/O monitor: <unowned>
    Alarm monitor: <unowned>
        Waiting to be notified:
            <unknown thread> (0x2bd48)
    Thread queue lock: owner "AWT-EventQueue-0" (0x2d9400) 1 entry
        Waiting to be notified:
            "Thread-1" (0x26a30)
    Monitor registry: owner "AWT-EventQueue-0" (0x2d9400) 1 entry