Issues with Installing OCaml and OPAM on Windows 10

[SitaGanesh]

Description:
I encountered multiple issues while trying to install OCaml and OPAM on my Windows 10 system. Despite following the recommended steps, I faced several errors related to the installation of the OCaml base compiler and other dependencies. Below are the details of the steps I followed and the errors I encountered.

Steps to Reproduce:

1. Installed Cygwin with the following packages:
   • gcc-core
   • make
   • autoconf
   • automake
   • libtool
2. Added Cygwin's bin directory to the system PATH.
3. Installed OPAM and initialized it using:

   `opam init`
   

4. Attempted to create a new OPAM switch with OCaml version 4.12.0:
   opam switch create 4.12.0 --jobs=1
5. Encountered the following error during the switch creation:
   configure: error: no acceptable C compiler found in $PATH

Error Logs:

=== ERROR while compiling ocaml-base-compiler.4.12.0 =========================
context     2.3.0 | win32/x86_64 |  | https://opam.ocaml.org#3531767c50e60953b103a19f8a8a461a0d57fe77
path        ~\AppData\Local\opam\4.12.0\.opam-switch\build\ocaml-base-compiler.4.12.0   
command     ~\AppData\Local\opam\4.12.0\.opam-switch\build\ocaml-base-compiler.4.12.0\./configure --prefix=C:\Users\User\AppData\Local\opam\4.12.0 -C
exit-code   1
env-file    ~\AppData\Local\opam\log\ocaml-base-compiler-13196-4a252b.env
output-file ~\AppData\Local\opam\log\ocaml-base-compiler-13196-4a252b.out
### output ###
[...]
checking build system type... x86_64-pc-cygwin
checking host system type... x86_64-pc-cygwin
checking target system type... x86_64-pc-cygwin
checking for ld... no
checking for link... link
checking how to print strings... printf
checking for gcc... no
checking for cc... no
checking for cl.exe... no
configure: error: in `/cygdrive/c/Users/User/AppData/Local/opam/4.12.0/.opam-switch/build/ocaml-base-compiler.4.12.0':
configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details
`

Additional Information:

• Windows 10 OS
• Cygwin installed with the required packages
• OPAM version: 2.3.0
• OCaml version attempted: 4.12.0

Expected Behavior: The OCaml base compiler and other dependencies should install successfully without errors.

Actual Behavior: The installation fails with errors indicating that no acceptable C compiler was found in the $PATH.

[punchagan]

@SitaGanesh Thanks for reporting the issue. It may be better to report it on the opam GitHub repository, possibly with more debug information like your $PATH, etc.