Resolving dlib Compilation Error: Undeclared 'ssize_t' on Windows
Error Description
During dlib installatoin via python setup.py install on Windows with Python 3.10, compilation fails with:
error C2065: "ssize_t": undeclared identifier
This occurs in the pybind11 header file within dlib's dependencies.
Soultion
Modify the numpy.h header in dlib's pybind11 include directory:
- Locate the target section in
dlib/external/pybind11/include/pybind11/numpy.h:
#if defined(_MSC_VER)
# pragma warning(push)
# pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
#endif
- Replace with:
#if defined(_MSC_VER)
# pragma warning(push)
# pragma warning(disable: 4127) // Suppress constant conditional warning
typedef SSIZE_T ssize_t;
#endif
- Re-run installation:
python setup.py install
The build should complete successfully after applying this patch.
