jackpot-miner/BUILD-windows.md

Building jackpotminer on Windows

The miner builds on Windows with no external GPU SDKs. The CUDA driver and NVML are loaded at runtime (dlopen/LoadLibrary), and the OpenCL import library is generated at build time from windows/OpenCL.def — so you don't need the CUDA Toolkit, an OpenCL SDK, or any vendor libraries to compile. The whole codebase (miner + the jackpotminer-config GUI) is verified to compile for x86_64-pc-windows-*.

Prerequisites

• Rust (https://rustup.rs). The default target is x86_64-pc-windows-msvc.
• MSVC build tools — Visual Studio 2019/2022 or the standalone Build Tools for Visual Studio with the “Desktop development with C++” workload (gives link.exe, lib.exe, and the Windows SDK).
  • Build from a “x64 Native Tools Command Prompt for VS” (or any shell where the MSVC environment is active) so lib.exe is found. cargo also locates it automatically via the registry in most cases.
• (Alternative toolchain) the GNU target x86_64-pc-windows-gnu works too, with MinGW-w64 on PATH (provides dlltool and the linker).

No CUDA Toolkit and no OpenCL SDK are required.

Build

:: Default: OpenCL + CUDA backends + the GUI config tool
cargo build --release

:: Miner only (no GUI), both GPU backends
cargo build --release --no-default-features --features gpu,cuda

:: OpenCL only (AMD / Intel / NVIDIA)
cargo build --release --no-default-features --features gpu

:: NVIDIA only — needs nothing external at build time (CUDA is dlopen'd)
cargo build --release --no-default-features --features cuda

Outputs: target\release\jackpotminer.exe (and jackpotminer-config.exe with the default features).

How the OpenCL build dependency is avoided

ocl/cl-sys link OpenCL (#[link(name = "OpenCL")]), which normally needs an OpenCL.lib from a vendor SDK. Instead, build.rs generates a vendor-neutral import library from windows/OpenCL.def:

• MSVC: lib.exe /def:windows\OpenCL.def /out:OpenCL.lib /machine:X64
• GNU: dlltool -d windows/OpenCL.def -l libOpenCL.a -m i386:x86-64

and puts it on the link search path. The import library only forwards to OpenCL.dll, which the GPU driver provides at runtime. If the toolchain tool isn’t on PATH, build.rs prints a warning and the link step fails with a clear message (compilation/cargo check still works).

Distribution

Statically link the MSVC C runtime so users don’t need the VC++ redistributable:

set RUSTFLAGS=-C target-feature=+crt-static
cargo build --release

Runtime dependencies (on the mining machine)

• OpenCL.dll — the ICD loader, installed with any GPU driver (AMD/NVIDIA/ Intel). Required for the OpenCL backend.
• nvcuda.dll + nvml.dll — installed with the NVIDIA driver. Loaded on demand for the CUDA backend; absent on AMD-only machines, where the miner simply reports no CUDA devices.
• The VC++ runtime, unless you built with +crt-static.

A cuda-enabled binary still starts on a machine with no NVIDIA driver.

Building Windows binaries without a Windows machine

GitHub Actions (recommended)

name: windows
on: [push, workflow_dispatch]
jobs:
  build:
    runs-on: windows-latest          # MSVC + lib.exe already on PATH
    steps:
      - uses: actions/checkout@v4
      - uses: dtolnay/rust-toolchain@stable
      - run: cargo build --release --features gpu,cuda
        env:
          RUSTFLAGS: -C target-feature=+crt-static
      - uses: actions/upload-artifact@v4
        with:
          name: jackpotminer-windows
          path: target/release/*.exe

Cross-compile from Linux (GNU target)

rustup target add x86_64-pc-windows-gnu
sudo pacman -S mingw-w64           # or your distro's mingw-w64 (gives dlltool + linker)
cargo build --release --target x86_64-pc-windows-gnu --no-default-features --features gpu,cuda

The MSVC target can’t be linked from Linux. The GUI config tool (eframe) is easiest to build natively on Windows.

Status / caveats

• Compilation for Windows is verified here via cargo check --target x86_64-pc-windows-gnu (default features, and gpu,cuda).
• The OpenCL import-library linking uses the standard lib.exe/dlltool technique; validate it with an actual Windows (or MinGW cross) build, which needs those tools present.
• relaunch_in_terminal (reopen-in-a-terminal on GUI launch) is Linux-only; harmless on Windows, where double-clicking a console binary already opens a console.