Ruby Debug showing very repeditive error in impl.rb

[nathan-nhm]

While trying to debug other things, I'm running ruby with RUBYOPT=-d

Exception 'SyntaxError' at ~/Ruby3421_x64/lib/ruby/gems/3.4.0/gems/forwardable-1.3.3/lib/forwardable/impl.rb:6 - ~/Ruby3421_x64/lib/ruby/gems/3.4.0/gems/forwardable-1.3.3/lib/forwardable/impl.rb:6: syntax errors found
> 6 | BEGIN{throw tag}; ().pos=
    |                         ^ expected an expression after `=`
    |                          ^ unexpected end-of-input, assuming it is closing the parent top level context

Exception 'SyntaxError' at ~/Ruby3421_x64/lib/ruby/gems/3.4.0/gems/forwardable-1.3.3/lib/forwardable/impl.rb:6 - ~/Ruby3421_x64/lib/ruby/gems/3.4.0/gems/forwardable-1.3.3/lib/forwardable/impl.rb:6: syntax errors found
> 6 | BEGIN{throw tag}; ().sync=
    |                          ^ expected an expression after `=`
    |                           ^ unexpected end-of-input, assuming it is closing the parent top level context

A sample with a dozen instances, normally hidden by the begin/rescue in impl.rb

I take it the eval() currently used hates the '=' of setter methods?