findlib sometimes cannot be built on Windows

I'm not sure if this is the right place to report this, but there seems to be a nondeterministic issue with the setup of OCaml/opam on Windows:

<><>Processing actions<><><><><><><><><><><><><><><><><><><><><><><><><><><><>
[ERROR] The compilation of ocamlfind failed at "D:\\cygwin\\bin\\make.exe opt".
-> installed conf-findutils.1
-> installed conf-gmp.4
-> installed dune.3.3.1
#===ERRORwhile compiling ocamlfind.1.9.5====================================#
#context     2.0.10 | win32/x86_64 | ocaml-variants.4.11.1+mingw64c | git+https://github.com/fdopen/opam-repository-mingw.git#opam2
#path        D:/a/fiat-crypto/fiat-crypto/_opam/.opam-switch/build/ocamlfind.1.9.5
#command     D:\cygwin\bin\make.exe opt
#exit-code   2
#env-file    D:/.opam/log/ocamlfind-1[38](https://github.com/mit-plv/fiat-crypto/runs/7199984869?check_suite_focus=true#step:14:39)4-03b1a4.env
#output-file D:/.opam/log/ocamlfind-1384-03b1a4.out
### output ###
# for p in findlib; do ( cd src/$p; /usr/bin/make opt ) || exit; done
# make[1]: Entering directory '/cygdrive/d/a/fiat-crypto/fiat-crypto/_opam/.opam-switch/build/ocamlfind.1.9.5/src/findlib'
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c findlib_config.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_split.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_metatoken.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_meta.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_metascanner.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_topo.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_package_base.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c findlib.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_args.ml
# ocamlopt -I +compiler-libs -g -opaque  -I +unix -I +dynlink -c fl_lint.ml
# ocamlopt -I +compiler-libs -g -a -o findlib.cmxa findlib_config.cmx fl_split.cmx fl_metatoken.cmx fl_meta.cmx fl_metascanner.cmx fl_topo.cmx fl_package_base.cmx findlib.cmx fl_args.cmx fl_lint.cmx
# if [ 1 -gt 0 ]; then \
#     ocamlopt -I +compiler-libs -g -shared -o findlib.cmxs findlib_config.cmx fl_split.cmx fl_metatoken.cmx fl_meta.cmx fl_metascanner.cmx fl_topo.cmx fl_package_base.cmx findlib.cmx fl_args.cmx fl_lint.cmx; \
# fi
# ** Fatal error: Cannot run cygpath -m findlib.cmxs
# File "caml_startup", line 1:
# Error: Error during linking (exit code 2)
# make[1]: *** [Makefile:71: findlib.cmxa] Error 2
# make[1]: Leaving directory '/cygdrive/d/a/fiat-crypto/fiat-crypto/_opam/.opam-switch/build/ocamlfind.1.9.5/src/findlib'
# make: *** [Makefile:18: opt] Error 2
<><>Error report<><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+- The following actions failed
| - build ocamlfind 1.9.5
+- 
+- The following changes have been performed (the rest was aborted)
| - install conf-findutils 1
| - install conf-gmp       4
| - install dune           3.3.1
+- 
[NOTE] Pinning command successful, but your installed packages may be out of sync.

https://github.com/mit-plv/fiat-crypto/runs/7199984869?check_suite_focus=true#step:14:68

Start with the linked GitHub Actions run and the ocamlfind build log, then inspect the Makefile target reported at line 71 and the failing cygpath invocation. Reproduce the intermittent Windows build failure and establish a reliable successful build of ocamlfind under the shown OCaml/opam environment.