dash/doc/build-windows.md

WINDOWS BUILD NOTES

Below are some notes on how to build Bitcoin Core for Windows.

Most developers use cross-compilation from Ubuntu to build executables for Windows. This is also used to build the release binaries.

While there are potentially a number of ways to build on Windows (for example using msys / mingw-w64), using the Windows Subsystem For Linux is the most straightforward. If you are building with another method, please contribute the instructions here for others who are running versions of Windows that are not compatible with the Windows Subsystem for Linux.

Compiling with Windows Subsystem For Linux

With Windows 10, Microsoft has released a new feature named the Windows Subsystem for Linux. This feature allows you to run a bash shell directly on Windows in an Ubuntu-based environment. Within this environment you can cross compile for Windows without the need for a separate Linux VM or server.

This feature is not supported in versions of Windows prior to Windows 10 or on Windows Server SKUs. In addition, it is available only for 64-bit versions of Windows.

To get the bash shell, you must first activate the feature in Windows.

1. Turn on Developer Mode

• Open Settings -> Update and Security -> For developers
• Select the Developer Mode radio button
• Restart if necessary

2. Enable the Windows Subsystem for Linux feature

• From Start, search for "Turn Windows features on or off" (type 'turn')
• Select Windows Subsystem for Linux (beta)
• Click OK
• Restart if necessary

3. Complete Installation

• Open a cmd prompt and type "bash"
• Accept the license
• Create a new UNIX user account (this is a separate account from your Windows account)

After the bash shell is active, you can follow the instructions below, starting with the "Cross-compilation" section. Compiling the 64-bit version is recommended but it is possible to compile the 32-bit version.

Cross-compilation

These steps can be performed on, for example, an Ubuntu VM. The depends system will also work on other Linux distributions, however the commands for installing the toolchain will be different.

First, install the general dependencies:

sudo apt-get install build-essential libtool autotools-dev automake pkg-config bsdmainutils curl

A host toolchain (build-essential) is necessary because some dependency packages (such as protobuf) need to build host utilities that are used in the build process.

Building for 64-bit Windows

To build executables for Windows 64-bit, install the following dependencies:

sudo apt-get install g++-mingw-w64-x86-64 mingw-w64-x86-64-dev

Then build using:

cd depends
make HOST=x86_64-w64-mingw32
cd ..
./autogen.sh # not required when building from tarball
CONFIG_SITE=$PWD/depends/x86_64-w64-mingw32/share/config.site ./configure --prefix=/
make

Building for 32-bit Windows

To build executables for Windows 32-bit, install the following dependencies:

sudo apt-get install g++-mingw-w64-i686 mingw-w64-i686-dev 

Then build using:

cd depends
make HOST=i686-w64-mingw32
cd ..
./autogen.sh # not required when building from tarball
CONFIG_SITE=$PWD/depends/i686-w64-mingw32/share/config.site ./configure --prefix=/
make

Depends system

For further documentation on the depends system see README.md in the depends directory.

Installation

After building using the Windows subsystem it can be useful to copy the compiled executables to a directory on the windows drive in the same directory structure as they appear in the release .zip archive. This can be done in the following way. This will install to c:\workspace\bitcoin, for example:

make install DESTDIR=/mnt/c/workspace/bitcoin