Hi,

when compiling GiNaC (latest version from git master) with MSVC (19.29.30139 for x64) it stumbles over the following code in lst.h/lst.cpp:

lst.h line 35:
template<> registered_class_info lst::reg_info;

lst.cpp line 28:
template <> GINAC_IMPLEMENT_REGISTERED_CLASS_OPT_T(lst, basic,
  print_func<print_context>(&lst::do_print).
  print_func<print_tree>(&lst::do_print_tree))

and says:

lst.cpp(28): error C2766: explicit specialization; 'reg_info' has already been defined

exprseq.h/.cpp has the same issue.

A solution seems to be to remove the code in lst.cpp and replace the code in lst.h with it. That is

lst.h:
template <> GINAC_IMPLEMENT_REGISTERED_CLASS_OPT_T(lst, basic,
  print_func<print_context>(&lst::do_print).
  print_func<print_tree>(&lst::do_print_tree))

This compiles fine and all checks pass, but it does seem wrong to have the GINAC_IMPLEMENT_REGISTERED_CLASS_OPT_T in a header file.

What is the right way to deal with this error?

Thanks,

Jan Rheinländer