glr2.cc compile errors under Windows

glr2.cc  does not work for me. I get compile errors with the resultant parser
and scanner files that are generated.

To be honest, I'm not quite sure where to begin in regards to figuring out the problem.

From what I've read:

"It should be upward compatible in terms of interface, feature and
performance to "glr.cc". To try it out, simply use
%skeleton "glr2.cc"

Since I wanted to look at the %merge feature again, I decided to update
everything and give that a try. I am not sure if I am messing something up
or if there is an issue somewhere.

Here is a summary of the situation:

I'm running Windows 10, developing with MSVC 2022 and using cygwin for flex/bison.

I used to use win_flex/win_bison on sourceforge but it hasn't been updated
for a year, and I wanted to use the latest versions of flex and bison.

I installed the 64 bit version of cygwin and installed flex/bison thru their
setup interface. The flex/bison versions are:

flex 2.6.4
bison (GNU Bison) 3.8.2

I then added the bin directory to my PATH and copied flexlexer.h into another
directory so I could set my MSVC "Additional include dir" to it.
(I can't set MSVC directly to the /usr/include since MSVC was using additional
files from it which caused multiple errors.

Anyways, that worked fine. After some minor changes for MSVC, I verified everything
was working by recompiling my source (using glr.cc) and everything works as before.

I then set my parser's skeleton to glr2.cc
Flex and bison do their work, and report the expected amount of s/r r/r conflicts.
I then compile the generated code but I get multiple errors compiling both files.

1>parser.cpp
1>D:\data\c\gen\runtime\parser.h(480,1): error C2535: 'gen::Parser::basic_symbol<Base> &gen::Parser::basic_symbol<Base>::operator =(const gen::Parser::basic_symbol<Base> &)': member function already defined or declared
1>D:\data\c\gen\runtime\parser.h(435): message : see declaration of 'gen::Parser::basic_symbol<Base>::operator ='
1>D:\data\c\gen\runtime\parser.h(482): message : see reference to class template instantiation 'gen::Parser::basic_symbol<Base>' being compiled
1>D:\data\c\gen\runtime\parser.h(480,1): error C2535: 'gen::Parser::basic_symbol<gen::Parser::by_kind> &gen::Parser::basic_symbol<gen::Parser::by_kind>::operator =(const gen::Parser::basic_symbol<gen::Parser::by_kind> &)': member function already defined or declared
1>D:\data\c\gen\runtime\parser.h(435): message : see declaration of 'gen::Parser::basic_symbol<gen::Parser::by_kind>::operator ='
1>D:\data\c\gen\runtime\parser.h(529): message : see reference to class template instantiation 'gen::Parser::basic_symbol<gen::Parser::by_kind>' being compiled
1>D:\data\c\gen\runtime\scanner.h(35,55): error C2039: 'semantic_type': is not a member of 'gen::Parser'
1>D:\data\c\gen\runtime\parser.h(122): message : see declaration of 'gen::Parser'

... etc (the other messages look like msvc is past the point of generating meaningful messages).

Does anyone have experience with a similar setup?
I wonder if I messed something up or should I send this to bug-bison?
Any guidance would be appreciated.

Thanks