Why can't a null-reference exception name the object that has a null reference?

Question

It seems to me that a lot of my debugging time is spent chasing down null-reference exceptions in complex statements. For instance:

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Answer 1

For languages like Java that are compiled to bytecode that gets interpreted by a VM, suppose you have a class X with a field x, and its value is null for a certain reference. If you write

x.foo()

the bytecode might look like this:

push Xref           >> top of stack is ref to instance of X with X.x = null
getField x          >> pops Xref, pushes 'null' on the stack
invokeMethod foo    >> pops 'null' -> runtime exception

The point is that the operation that needs a non-null reference on the stack to operate on it, like invokeMethod in the example, cannot and does not know where that null reference came from.