Undefined reference to `__imp_caml_startup'

I use OCaml for Windows - Installation in my cygwin env.

but when i try to follow the example of OCaml - Interfacing C with OCaml, i got the error like this:

/usr/lib/gcc/x86_64-pc-cygwin/11/…/…/…/…/x86_64-pc-cygwin/bin/ld: /tmp/ccFApXK2.o:main.c:(.text+0x1e): undefined reference to __imp_caml_startup' /usr/lib/gcc/x86_64-pc-cygwin/11/../../../../x86_64-pc-cygwin/bin/ld: mod.a(modwrap.o):modwrap.c:(.text+0x1e): undefined reference to __imp_caml_callback’
/usr/lib/gcc/x86_64-pc-cygwin/11/…/…/…/…/x86_64-pc-cygwin/bin/ld: mod.a(modwrap.o):modwrap.c:(.text+0x39): undefined reference to __imp_caml_named_value' /usr/lib/gcc/x86_64-pc-cygwin/11/../../../../x86_64-pc-cygwin/bin/ld: mod.a(modwrap.o):modwrap.c:(.text+0x6e): undefined reference to __imp_caml_callback’
/usr/lib/gcc/x86_64-pc-cygwin/11/…/…/…/…/x86_64-pc-cygwin/bin/ld: mod.a(modwrap.o):modwrap.c:(.text+0x89): undefined reference to `__imp_caml_named_value’

thanks