i more information about gobject datastructures in gtk than cl-cffi-gtk provides. i try to setup the cffi groveller
this is the output that i need:

/dev/shm/.cache/common-lisp/sbcl-1.2.5-linux-x64/home/martin/cl-cffi-gtk-from-repl/gtk-grovel.processed-grovel-file
(cffi:defcstruct (%gtk-entry :size 40))
(cl:defconstant size-of-%gtk-entry (cffi:foreign-type-size '(:struct %gtk-entry)))
describe the new code in the readme
figure out how to read the sizes of gobject classes after they were grovelled by cffi
it's easier if the groveller definitions are in custom-class namespace and not in ..internal
now the derived structs have the correct size
register static works, cleanup