How do I found out which .i rule/pattern generates a specific (illegal) C++ code fragment?

I've abandoned my effort to use .i files for OCC (OpenCascade) from the occpython project because 
it looks like there is a lot of Python specific stuff in there that would have to be recreated for Java
and I don't have the appetite for that.

Instead I went back to occjava which I successfully compiled some years ago.

Now some bit rot has set in and when I try to compile it I get:

[ 50%] Building CXX object CMakeFiles/OccJava.dir/src-java/org/jcae/opencascade/jni/OccJavaJAVA_wrap.cxx.o
/Users/nyholku/jcae/occjava/src-java/org/jcae/opencascade/jni/OccJavaJAVA_wrap.cxx:5123:29: error: taking the address of a temporary object of type 'TopoDS_Shape' [-Waddress-of-temporary]
  result = (TopoDS_Shape *) &((BRepBuilderAPI_ModifyShape const *)arg1)->ModifiedShape((TopoDS_Shape const &)*arg2);
                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
make[2]: *** [CMakeFiles/OccJava.dir/src-java/org/jcae/opencascade/jni/OccJavaJAVA_wrap.cxx.o] Error 1


As far as I have been able to find out above actually is illegal (at least today) even though it used to compile a few years back with clang.

The actual SWIG generated code is:



SWIGEXPORT jlong JNICALL Java_org_jcae_opencascade_jni_OccJavaJNI_BRepBuilderAPI_1ModifyShape_1modifiedShape(JNIEnv *jenv, jclass jcls, jlong jarg1, jobject jarg1_, jlong jarg2, jobject jarg2_) {
  jlong jresult = 0 ;
  BRepBuilderAPI_ModifyShape *arg1 = (BRepBuilderAPI_ModifyShape *) 0 ;
  TopoDS_Shape *arg2 = 0 ;
  TopoDS_Shape *result = 0 ;

  (void)jenv;
  (void)jcls;
  (void)jarg1_;
  (void)jarg2_;
  arg1 = *(BRepBuilderAPI_ModifyShape **)&jarg1;
  arg2 = *(TopoDS_Shape **)&jarg2;
  if (!arg2) {
    SWIG_JavaThrowException(jenv, SWIG_JavaNullPointerException, "TopoDS_Shape const & reference is null");
    return 0;
  }
  result = (TopoDS_Shape *) &((BRepBuilderAPI_ModifyShape const *)arg1)->ModifiedShape((TopoDS_Shape const &)*arg2);
  {
    if(result->IsNull())

If I hand edit this to:

  TopoDS_Shape result;
...
  result = BRepBuilderAPI_ModifyShape const *)arg1)->ModifiedShape((TopoDS_Shape const &)*arg2);  {
  {
	  if(result.IsNull())

The code compiles and seems to work (not sure if above piece of code get executed though).

Now, my question is how do I found out which .i rule/pattern generates above illegal C++ code fragment?

wbr Kusti