[tcljava-user] TclBlend crash : JNI Panic

[Jean-Francois M. <jea...@st...>]

Hi,

I have a big trouble with TclBlend in my software.

The code crash with this stack trace :
JNI panic: native code passed a null object to a non-static method
        at tcl.lang.CObject.decrRefCount(Native Method)
        at tcl.lang.CObject.dispose(CObject.java:100)
        at tcl.lang.TclObject.setInternalRep(TclObject.java:107)
        at tcl.lang.FuncSig.get(FuncSig.java:249)
        at tcl.lang.JavaInvoke.callMethod(JavaInvoke.java:110)
        at tcl.lang.ReflectObject.cmdProc(ReflectObject.java:916)
        at tcl.lang.Interp.callCommand(Interp.java:953)

And sometimes the crash happens with this message :
JNI panic: native code passed a null object to a non-static method
        at tcl.lang.Interp.setResult(Native Method)
        at tcl.lang.Interp.setResult(Interp.java:736)
        at tcl.lang.TclException.<init>(TclException.java:89)
        at tcl.lang.TclException.<init>(TclException.java:155)
        at tcl.lang.ReflectObject.setReflectObjectFromAny(ReflectObject.j=
ava:691)
        at tcl.lang.ReflectObject.get(ReflectObject.java:783)
        at tcl.lang.JavaInvoke.convertTclObject(JavaInvoke.java:819)
        at tcl.lang.JavaInvoke.call(JavaInvoke.java:225)
        at tcl.lang.JavaInvoke.callMethod(JavaInvoke.java:109)
        at tcl.lang.ReflectObject.cmdProc(ReflectObject.java:888)
        at tcl.lang.Interp.callCommand(Interp.java:1071)

After some investigations, I found out a small script that behave almost =
like my application :

#!/home/crx005/mj42/debugTclBlend/local/bin/tclsh8.4

     # Max size of the JVM heap :
     set tclblend_init "-Xmx200m"

     # Init the JVM :
     package require java

     java::import -package java.util ArrayList

     # JNI Panic :

     set valuesList [java::new ArrayList]

     set list2 {}
     for { set i 0 } { $i < 50000 } { incr i } {
         set list1  [ list \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] \
             nbx   [$valuesList size] ]
         puts "$i"
         lappend list2 $list1
     }

And the message after the crash is :
JNI panic: native code passed a null object to a non-static method
        at tcl.lang.Interp.setResult(Native Method)
        at tcl.lang.ReflectObject.cmdProc(ReflectObject.java:888)
        at tcl.lang.Interp.callCommand(Interp.java:1071)

Whatever method you called on the object (valuesList), the crash always h=
appens within the same iteration.
Other method calls, together (size and isEmpty for example) or not, or us=
ing another object (for example Integer and intValue
method) doesn't change the behavior.

Moreover, the more the Java method is called, the faster the crash happen=
s.

For the first crash, when I look at the code tclBlend/src/native/javaObj.=
c,  function  FreeTclObject, it seems impossible to call
(*env)->CallVoidMethod(env, object, java.release); with a null object, be=
cause this function is only called if object is not null.

So, I tought, may be it was a problem with multi-thread and I decided to =
try TclBlend 1.3.1.

But the problem remains the same with TclBend 1.3.1 and 1.2.6 on Solaris =
2.6 and 2.8.

Any idea ?

Thanks.


Environment :

OS : Solaris 2.6 (SunOS crx120 5.6 Generic_105181-29 sun4u sparc SUNW,Ult=
ra-4) and 2.8 (SunOS crx246 5.8 Generic_108528-13 sun4u
sparc
SUNW,Ultra-5_10)

Tcl/Tk 8.3 and TclBlend 1.2.6 (+ my own patch to correct another bug : "t=
cl.lang.TclRuntimeError: (find) table entry
"analysis.dataset.Parameter.10023470" mapped to an invalid entry...") com=
piled on Solaris 2.6

Tcl/Tk 8.4.6 + thread 2.5.2 extension and TclBlend 1.3.1 compiled on Sola=
ris 2.6
Java 1.2.2 (Solaris VM (build Solaris_JDK_1.2.2_10, native threads, sunwj=
it))

Compiler : gcc 3.2.1 (Configured with: ./configure --prefix=3D/soft/tools=
 --with-gnu-ld --with-gnu-as  Thread model: posix)




--
Jean-Fran=E7ois.