The build of sphinxbase-5-0.17.prealpha is failing against SWIG 4.2.0 in Fedora rawhide/40.

sphinxbase_wrap.c: In function '_wrap_NGramModel_add_class':
sphinxbase_wrap.c:5823:19: error: implicit declaration of function 'SWIG_Python_str_AsChar'; did you mean 'SWIG_Python_str_FromChar'? [-Wimplicit-function-declaration]
 5823 |         arg5[i] = SWIG_Python_str_AsChar(o);
      |                   ^~~~~~~~~~~~~~~~~~~~~~
      |                   SWIG_Python_str_FromChar
sphinxbase_wrap.c:5823:17: error: assignment to 'char *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
 5823 |         arg5[i] = SWIG_Python_str_AsChar(o);
      |                 ^
sphinxbase_wrap.c:5842:9: error: implicit declaration of function 'SWIG_Python_str_DelForPy3'; did you mean 'SWIG_Python_str_FromFormat'? [-Wimplicit-function-declaration]
 5842 |         SWIG_Python_str_DelForPy3(arg5[i]);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~
      |         SWIG_Python_str_FromFormat
sphinxbase_wrap.c: In function '_wrap_NGramModel_prob':
sphinxbase_wrap.c:5889:17: error: assignment to 'char *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
 5889 |         arg3[i] = SWIG_Python_str_AsChar(o);
      |                 ^
make[2]: Leaving directory '/builddir/build/BUILD/sphinxbase-5prealpha/swig/python'

SWIG upstream proposed a solution
https://github.com/swig/swig/issues/2777#issuecomment-1909058619

Reproducible: Always