tcl8.5.10rc1 segfault and backtrace

emiliano@beaujolais:~/src/tcl8.5.10/unix$ gdb ./tcltest -core tcltest.core
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This GDB was configured as "x86_64--netbsd"...
Reading symbols from /home/emiliano/src/tcl8.5.10/unix/libtcl8.5.so...done.
Loaded symbols for /home/emiliano/src/tcl8.5.10/unix/libtcl8.5.so
Reading symbols from /usr/lib/libm.so.0...done.
Loaded symbols for /usr/lib/libm.so.0
Reading symbols from /usr/lib/libc.so.12...done.
Loaded symbols for /usr/lib/libc.so.12
Reading symbols from /usr/libexec/ld.elf_so...done.
Loaded symbols for /usr/libexec/ld.elf_so
Core was generated by `tcltest'.
Program terminated with signal 11, Segmentation fault.
#0  0x00007f7ff78d5440 in TclListObjCopy (interp=0x0, listPtr=0x7f7ff7744a50)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclListObj.c:416
416         DupListInternalRep(listPtr, copyPtr);
(gdb) bt
#0  0x00007f7ff78d5440 in TclListObjCopy (interp=0x0, listPtr=0x7f7ff7744a50)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclListObj.c:416
#1  0x00007f7ff78e38d0 in NsEnsembleImplementationCmd (clientData=0x7f7ff7705260, 
    interp=0x7f7ff7723800, objc=2, objv=0x7f7ff6f1e9e8)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclNamesp.c:6196
#2  0x00007f7ff7836e18 in TclEvalObjvInternal (interp=0x7f7ff7723800, objc=2, 
    objv=0x7f7ff6f1e9e8, command=0xffffffffffffffff <Address 0xffffffffffffffff out of bounds>, 
    length=-1, flags=0) at /home/emiliano/src/tcl8.5.10/unix/../generic/tclBasic.c:3699
#3  0x00007f7ff789e998 in TclExecuteByteCode (interp=0x7f7ff7723800, codePtr=0x7f7ff77982d0)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclExecute.c:2416
#4  0x00007f7ff78faae4 in TclObjInterpProcCore (interp=0x7f7ff7723800, 
    procNameObj=0x7f7ff77b6360, skip=1, errorProc=0x7f7ff78fb18f <MakeProcError>)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclProc.c:1761
#5  0x00007f7ff78faa17 in TclObjInterpProc (clientData=0x7f7ff77c7200, interp=0x7f7ff7723800, 
    objc=2, objv=0x7f7ff6f1e8f8) at /home/emiliano/src/tcl8.5.10/unix/../generic/tclProc.c:1651
#6  0x00007f7ff7836e18 in TclEvalObjvInternal (interp=0x7f7ff7723800, objc=2, 
    objv=0x7f7ff6f1e8f8, command=0xffffffffffffffff <Address 0xffffffffffffffff out of bounds>, 
    length=-1, flags=0) at /home/emiliano/src/tcl8.5.10/unix/../generic/tclBasic.c:3699
#7  0x00007f7ff789e998 in TclExecuteByteCode (interp=0x7f7ff7723800, codePtr=0x7f7ff77982d0)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclExecute.c:2416
#8  0x00007f7ff78faae4 in TclObjInterpProcCore (interp=0x7f7ff7723800, 
    procNameObj=0x7f7ff77b6360, skip=1, errorProc=0x7f7ff78fb18f <MakeProcError>)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclProc.c:1761
#9  0x00007f7ff78faa17 in TclObjInterpProc (clientData=0x7f7ff77c7200, interp=0x7f7ff7723800, 
    objc=2, objv=0x7f7ff6f1e808) at /home/emiliano/src/tcl8.5.10/unix/../generic/tclProc.c:1651
#10 0x00007f7ff7836e18 in TclEvalObjvInternal (interp=0x7f7ff7723800, objc=2, 
    objv=0x7f7ff6f1e808, command=0xffffffffffffffff <Address 0xffffffffffffffff out of bounds>, 
    length=-1, flags=0) at /home/emiliano/src/tcl8.5.10/unix/../generic/tclBasic.c:3699
#11 0x00007f7ff789e998 in TclExecuteByteCode (interp=0x7f7ff7723800, codePtr=0x7f7ff77982d0)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclExecute.c:2416
#12 0x00007f7ff78faae4 in TclObjInterpProcCore (interp=0x7f7ff7723800, 
    procNameObj=0x7f7ff77b6360, skip=1, errorProc=0x7f7ff78fb18f <MakeProcError>)
    at /home/emiliano/src/tcl8.5.10/unix/../generic/tclProc.c:1761

And repeats ad nauseam