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3d98a6ef5c
The `memset` function and bitwise manipulation only apply to POD types that do not require initialization, otherwise resulting in UB. We currently violate this in `ptrue` and `pzero`, we assume bitmasks for `pselect`, and bitwise operations are applied byte-by-byte in the generic implementations. This is causing issues for scalar types that do require initialization or that contain non-POD info such as pointers (#2201). We either break them, or force specializations of these functions for custom scalars, even if they are not vectorized. Here we modify these functions for scalars only - instead using only scalar operations: - `pzero`: `Scalar(0)` for all scalars. - `ptrue`: `Scalar(1)` for non-trivial scalars, bitset to one bits for trivial scalars. - `pselect`: ternary select comparing mask to `Scalar(0)` for all scalars - `pand`, `por`, `pxor`, `pnot`: use operators `&`, `|`, `^`, `~` for all integer or non-trivial scalars, otherwise apply bytewise. For non-scalar types, the original implementations are used to maintain compatibility and minimize the number of changes. Fixes #2201.