[BUG]: Coverity issue in dispatcher: Possible dereferencing null pointer self_value_and_holder.type

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What version (or hash if on master) of pybind11 are you using?

2.10.2

Problem description

Coverity scan highlights possible explicit null pointer dereferencing in pybind11 dispatcher function in "pybind11.h".

The tools indicates that self_value_and_holder variable is initialized with default-constructed value_and_holder class which sets type pointer to NULL:

It stays NULL if overloads->is_constructor condition is false.

The type field is dereferenced here:

This maybe a false positive, since func.is_new_style_constructor might imply overloads->is_constructor, `but I could not determine that conclusively, hence this issue.

Reproducible example code

No response

Is this a regression? Put the last known working version here if it is.

Not a regression

Start in pybind11.h at the dispatcher function and trace value_and_holder initialization alongside the overloads->is_constructor and func.is_new_style_constructor conditions. Review the Coverity warning and relevant control flow to determine whether the dereference is safe; done means the warning is resolved or its false-positive status is conclusively established.