From 9c66a91826b56240626cb933abec0092aa499a96 Mon Sep 17 00:00:00 2001
From: Jan Svabenik <jan@svabi.ch>
Date: Thu, 19 Mar 2026 09:08:15 +0100
Subject: [PATCH] docs: clarify Windows CUDA build paths

---
 build-sdrplay.ps1          |  1 +
 build-windows-cuda-app.ps1 | 33 +++++++++++++++++++++++++++++++++
 docs/build-cuda.md         |  3 ++-
 3 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 build-windows-cuda-app.ps1

diff --git a/build-sdrplay.ps1 b/build-sdrplay.ps1
index c652eea..d2e4e88 100644
--- a/build-sdrplay.ps1
+++ b/build-sdrplay.ps1
@@ -44,6 +44,7 @@ if (Test-Path $cudaMingw) {
 Write-Host "Building with SDRplay + cuFFT support..." -ForegroundColor Cyan
 Write-Host "WARNING: this path still performs final Go linking through MinGW GCC." -ForegroundColor Yellow
 Write-Host "If CUDA kernel artifacts are MSVC-built, final link may fail due to mixed toolchains." -ForegroundColor Yellow
+Write-Host "Use build-cuda-windows.ps1 for CUDA artifact prep; use this script for the current MinGW-oriented app build path." -ForegroundColor Yellow
 
 $gccHost = Join-Path $gcc 'g++.exe'
 if (!(Test-Path $gccHost)) {
diff --git a/build-windows-cuda-app.ps1 b/build-windows-cuda-app.ps1
new file mode 100644
index 0000000..d540661
--- /dev/null
+++ b/build-windows-cuda-app.ps1
@@ -0,0 +1,33 @@
+$ErrorActionPreference = 'Stop'
+
+$msvcClDir = 'C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Tools\MSVC\14.29.30133\bin\Hostx64\x64'
+$vcvars = 'C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC\Auxiliary\Build\vcvars64.bat'
+$cudaBin = 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v13.2\bin'
+$cudaInc = 'C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v13.2\include'
+$sdrplayInc = 'C:\PROGRA~1\SDRplay\API\inc'
+$sdrplayLib = 'C:\PROGRA~1\SDRplay\API\x64'
+$cudaMingw = Join-Path $PSScriptRoot 'cuda-mingw'
+
+if (!(Test-Path (Join-Path $msvcClDir 'cl.exe'))) { throw "cl.exe not found at $msvcClDir" }
+if (!(Test-Path $vcvars)) { throw "vcvars64.bat not found at $vcvars" }
+if (!(Test-Path (Join-Path $cudaBin 'nvcc.exe'))) { throw "nvcc.exe not found at $cudaBin" }
+
+$env:PATH = "$msvcClDir;$cudaBin;" + $env:PATH
+$env:CGO_ENABLED = '1'
+$env:CC = 'cl.exe'
+$env:CXX = 'cl.exe'
+$env:CGO_CFLAGS = "-I$cudaInc -I$sdrplayInc"
+$env:CGO_LDFLAGS = "-L$sdrplayLib -lsdrplay_api -L$cudaMingw"
+
+Write-Host "Preparing CUDA kernel artifacts..." -ForegroundColor Cyan
+powershell -ExecutionPolicy Bypass -File tools\build-gpudemod-kernel.ps1
+if ($LASTEXITCODE -ne 0) { throw "kernel build failed" }
+
+Write-Host "Building Windows CUDA app with MSVC-oriented CGO path..." -ForegroundColor Cyan
+Write-Host "NOTE: This path is experimental. Go's CGO runtime still emits GCC-style warning flags that MSVC rejects in this environment." -ForegroundColor Yellow
+& cmd.exe /c "call `"$vcvars`" && go build -x -tags `"sdrplay,cufft`" ./cmd/sdrd"
+if ($LASTEXITCODE -ne 0) {
+  throw "windows cuda app build failed (current blocker: Go CGO emits GCC-style flags that cl.exe rejects, e.g. -Werror / -Wall / -fno-stack-protector)"
+}
+
+Write-Host "Done." -ForegroundColor Green
diff --git a/docs/build-cuda.md b/docs/build-cuda.md
index 454f4ff..b6c92ad 100644
--- a/docs/build-cuda.md
+++ b/docs/build-cuda.md
@@ -43,4 +43,5 @@ Prefer a GCC/NVCC-oriented build path:
 - `go test ./...` passes
 - `go test -tags cufft ./internal/demod/gpudemod` passes with NVCC/MSVC setup
 - `build-sdrplay.ps1` has progressed past the original invalid `#cgo LDFLAGS` issue
-- Remaining Windows blocker is now a toolchain mismatch between MSVC-built CUDA artifacts and MinGW final linking
+- Remaining Windows blocker in the default path is a toolchain mismatch between MSVC-built CUDA artifacts and MinGW final linking
+- Experimental full-MSVC CGO path (`build-windows-cuda-app.ps1`) also currently blocks because Go's CGO runtime emits GCC-style flags (`-Wall`, `-Werror`, `-fno-stack-protector`) that `cl.exe` rejects in this environment