sgi.com/tech/inventor/workarounds/mfnode.c

//
// This is a patch for the Inventor 2.0 SoMFNode field, which can core
// dump when its values are deleted.
//
// To apply this patch, compile this file into a .o and then link
// the .o before -lInventor.  The linker may give a warning.
// This is normal and expected.
//

#include 
#include 
#include 

////////////////////////////////////////////////////////////////////////
//
// This overrides the definition in SO_MFIELD_ALLOC_SOURCE() to
// keep track of references and auditors.
//
////////////////////////////////////////////////////////////////////////

void
SoMFNode::allocValues(int newNum)
{
    int	i;

    if (values == NULL)	{
	if (newNum > 0) {
	    values = new SoNode * [newNum];

	    // Make sure all pointers are initialized to NULL
	    for (i = 0; i < newNum; i++)
		values[i] = NULL;
	}
    }
    else {
	SoNode	**oldValues = values;

	if (newNum > 0) {
	    values = new SoNode * [newNum];
	    for (i = 0; i < num && i < newNum; i++)
		values[i] = oldValues[i];

	    // Initialize unused pointers to NULL
	    for (i = num; i < newNum; i++)
		values[i] = NULL;
	}
	else
	    values = NULL;

	// Free up any old stuff
	if (oldValues != NULL) {

	    // Remove auditors and references on unused values
	    for (i = newNum; i < num; i++) {
		if (oldValues[i] != NULL) {
		    oldValues[i]->removeAuditor(this, SoNotRec::FIELD);
		    oldValues[i]->unref();
		}
	    }

	    delete [] oldValues;
	}
    }

    num = maxNum = newNum;
}