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Building Windows binary with MSVC Ocaml 4.12 Using Docker Container

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Samson edited this page Jan 13, 2022 · 3 revisions

OCaml and opam native Windows Container images for Docker for Windows can be found in the ocaml/opam repository in the Docker Hub. This docker container provide the complete setup of OCaml/cygwin64/MSVC environment for building Unison binary in a Windows 64-bit machine. You can make use of this image by getting Docker Desktop for Windows installed. After installation be sure to switch Docker to Native Windows Containers before pulling the OCaml+opam Images for Docker for Windows. More details about this docker image announced here.

Steps to Setup and Builds

Before the installation, you may want to modify docker images storage location by modify C:\ProgramData\Docker\config\daemon.json (if this is a new installation you can create this file in advance like below):

{
    "experimental": false,
    "data-root": "D:\\DockerRoot"
}

If Docker Desktop for Windows already installed, you can append the "data-root" line, make it point to whatever drive path with enough disk space to hold the current OCaml+opam Images for Docker for Windows which is ~23.5GB. Be sure to append the ',' to the end of "experimental" line above or docker will crash upon re-start.

  1. Download and Install Docker Desktop for Windows (Requires Microsoft Windows 10 Professional or Enterprise 64-bit, or Windows 10 Home 64-bit with WSL 2.)

  2. Switch to Windows Container (open the Docker Desktop menu by right-click the Docker icon in the Notifications area or System tray then "Select Switch to Windows containers").

  3. Open a Windows Command Prompt.

  4. Get OCaml+opam Images for Docker for Windows docker image from Docker Hub ocaml/opam repository by enter:
    >docker pull ocaml/opam:windows-msvc-ocaml-4.12

  5. It will take quite some time, wait until process finish then enter:

     >docker images
 REPOSITORY   TAG                       IMAGE ID       CREATED        SIZE
 ocaml/opam   windows-msvc-ocaml-4.12   e69ba8b6bde7   3 months ago   23.5GB

  6. Now create a Container from the above image with Windows Host Folder Access by enter: (e.g. C:\Users\Your_Username\Downloads being mount to Docker container C:\cygwin64\home\opam\winfolder)

     >docker run -it -v C:\Users\Your_Username\Downloads:C:\cygwin64\home\opam\WinFolder ocaml/opam:windows-msvc-ocaml-4.12 ocaml-env exec --64 --ms=vs2019 -- cmd.exe

    (Note: Only execute this command once unless you need to create another container with the same image)

    You will enter the container environment like below:

     Microsoft Windows [Version 10.0.19041.1237]
 (c) Microsoft Corporation. All rights reserved.

 C:\cygwin64\home\opam>ls -l
 total 8
 drwxr-xr-x+ 1 Administrators SYSTEM        0 Oct  5 17:39 opam-repository
 drwx------+ 1 Unknown+User   Unknown+Group 0 Jan  8 08:21 winfolder

 C:\cygwin64\home\opam>ls -l winfolder
 total 540137
 -rwx------+ 1 Unknown+User Unknown+Group 519015312 Jan  1 16:12 'Docker Desktop Installer.exe'

    (As you can see Windows Host C:\Users\Your_Username\Downloads is being mounted to winfolder, files between host and container can be exchanged)

  7. We can exit the Docker Container environment by enter 'exit' or pressing CTRL-C.

  8. At this point you are re-enter the Windows Command Prompt.
    If you need to re-enter the container environment you need to know the container ID by enter:

     >docker ps --all --no-trunc
 CONTAINER ID                                                       IMAGE                                COMMAND                                                                           CREATED         STATUS                      PORTS     NAMES

 eb5a90d15d595b86cfd009a33821a385249448b46ef12d144bde2ef4220eecd0   ocaml/opam:windows-msvc-ocaml-4.12   "ocaml-env exec --64 --ms=vs2019 -- ocaml-env exec --64 --ms=vs2019 -- cmd.exe"   4 minutes ago   Exited (0) 33 seconds ago             silly_mahavira

  9. You only need the first 3 digits of the Container ID for re-start the container 'docker start' and re-connect the container 'docker attach' command.
    To restart the Container enter:

     >docker start eb5
 eb5
 >docker attach eb5

  10. You are now re-enter the Container environment, get unison source code by enter:

     >pwd
 /home/opam

 >git clone https://github.com/bcpierce00/unison.git
 Cloning into 'unison'...
 remote: Enumerating objects: 10301, done.
 remote: Counting objects: 100% (799/799), done.
 remote: Compressing objects: 100% (361/361), done.
 remote: Total 10301 (delta 486), reused 643 (delta 413), pack-reused 9502
 Receiving objects: 100% (10301/10301), 16.27 MiB | 1.77 MiB/s, done.
 Resolving deltas: 100% (7718/7718), done.

 >ls -l
 total 4
 drwxr-xr-x+ 1 ContainerAdministrator ContainerAdministrator 0 Jan  8 17:23 unison

    Congratulation, current version of unison "master" branch being downloaded to /home/opam/unison

  11. You can build unison binary from source by enter:

     >cd unison
 >make OSTYPE=cygwin

    If the process exit without error, you will find text user interface version of Windows 64-bit unison.exe and unison-fsmonitor.exe which were compiled with MSVC Ocaml-4.12 in /home/opam/unison/src:

     >ls -l unison/src/*.exe
 -rwxr-xr-x 1 ContainerAdministrator ContainerAdministrator 1428992 Jan 10 22:10 unison/src/unison-fsmonitor.exe
 -rwxr-xr-x 1 ContainerAdministrator ContainerAdministrator 3142144 Jan 10 22:10 unison/src/unison.exe

    To use the binary in Windows, msvcp140.dll is required and need copy to the same folder of unison.exe and unison-fsmonitor.exe, it can be found in this container here:

     >ls -l \BuildTools/VC/Tools/MSVC/14.29.30133/bin/Hostx86/x86/msvcp140.dll
 -rwxr-xr-x 1 ContainerAdministrator ContainerAdministrator 436600 Oct  5 17:18 '\BuildTools/VC/Tools/MSVC/14.29.30133/bin/Hostx86/x86/msvcp140.dll'
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