[CPyCppyy] Work around non-instantiable std::span iterators in GCC 15
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guitargeek
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@sponce To which releases would you need this packported? |
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Ideally LCG108 version, so 6.36 |
The libstdc++ (GCC >= 15) implements `std::span::iterator` using a private nested tag type, which makes the iterator non-instantiable by CallFunc-generated wrappers (the return type cannot be named without violating access rules). To preserve correct Python iteration semantics, this commit suggests to replace `begin()`/`end()` for `std::span` to return a custom pointer-based iterator instead. This avoids relying on `std::span::iterator` while still providing a real C++ iterator object that CPyCppyy can also wrap and expose via `__iter__`/`__next__`. A unit test is implemented based on the reproducers provided in root-project#18837. Closes root-project#18837.
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Test Results 23 files 23 suites 3d 15h 7m 20s ⏱️ For more details on these failures, see this check. Results for commit 253be89. |
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The libstdc++ (GCC >= 15) implements
std::span::iteratorusing a private nested tag type, which makes the iterator non-instantiable by CallFunc-generated wrappers (the return type cannot be named without violating access rules).To preserve correct Python iteration semantics, this commit suggests to replace
begin()/end()forstd::spanto return a custom pointer-based iterator instead. This avoids relying onstd::span::iteratorwhile still providing a real C++ iterator object that CPyCppyy can also wrap and expose via__iter__/__next__.A unit test is implemented based on the reproducers provided in #18837.
Closes #18837.