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+# Cross-compile Haskell on Linux targeting Windows using WINE
+
+This is aimed at Linux + Haskell + SDL2 + SDL2_Image, but it could be used for other cases.
+
+The main idea is to run the Windows version of all the needed compilers, on Linux using Wine. Cabal it is the entry point and it needs a script wrapping it so it runs with Wine and it can find the needed tools.
+
+It comes with no warranty, I'm documenting this for myself, and sharing it because *it is fiddly* and I hope that it might help other people.
+
+What is needed:
+
+- Cabal for Windows
+- GHC for Windows
+- MingGW-W64
+- SDL2 development for MinGW
+- pkg-config-lite for Windows
+- Wine on a Linux host (used Debian 11)
+- Patience and luck!
+
+Install Wine with:
+```
+sudo dpkg --add-architecture i386
+sudo apt-get update
+sudo apt-get install --no-install-recommends -y wine wine32 wine64
+```
+
+(or similar, I don't think it matters much as long it is a healthy Wine installation)
+
+## bootstrap script
+
+Edit the `bootstrap` script (you may need to adapt it to your system), and check that you are happy with the versions. It is a convenient way of setting up everything *for me*, but may not be useful for anybody else (also: it is a bit fragile).
+
+It requires: wget, 7z, unzip, tar and make (among other more common POSIX tools).
+
+The directory structure will be:
+
+- cache: where the requirements are downloaded.
+- packages: where the different Windows tools are setup.
+- workdir: where you should put your project (can be in any directory).
+- bin: contains `cabal-wine` helper.
+
+Currently I'm using:
+
+- Cabal 3.8.1.0
+- GHC 9.2.5
+- MinGW-W64 12.2.0
+- SDL2 2.26.3
+- SDL2_Image 2.6.3
+
+**Important**: you need to copy SDL2.dll and SDL2_image.dll to your `system32` directory in WINE, usually:
+```
+~/.wine/drive_c/windows/system32/
+```
+This is needed to compile sdl2 and sdl2-image. When you have your binary, you need to distribute those two DLLs with your .EXE.
+
+## Updating packages
+
+Run `bin/cabal-wine update` and Cabal should download the latest package list from hackage.
+
+## Building your peoject
+
+Get into workdir/your-project and run:
+
+`../../bin/cabal-wine build --builddir build`
+
+And it should work!
+
+## Troubleshooting
+
+**Extra logging**
+
+Pass `-v` option when running `cabal-wine` for exta information.
+
+**Failed to compile SDL2_Image**
+
+I have found that SDL2_Image is trying to include a SDL_Main when is not necessary.
+
+Once you have compiled sdl2, you can edit `packages/mingw64/x86_64-w64-mingw32/include/SDL2/SDL.h` and comment out the `#include "SDL_main.h"` line.
+
+There must be a better way of fixing this (perhaps a bug report to sdl2-image could help!).
+
+**Wine can't run the resulting binary**
+
+I use Debian stable, and the Wine version can be a bit old. It compiles fine, but running the resulting binary may not work. Try a more recent Wine version (tested with 8 and works fine).
+