fix(go): limit native bindings to supported targets

Author: anirudh-makuluri

sdks/go/README.md

@@ -19,6 +19,10 @@ For external projects, the explicit `--vendor` option lets the installer vendor
 the bindings before placing the library next to them, so the normal `go build`
 command finds it.
 
+Native bindings currently support Linux (`amd64`, `arm64`) and Apple Silicon
+macOS (`arm64`). Other platforms, including Windows, use the
+bindings-unavailable stub until a compatible native release is available.
+
 From a checkout of the bindings package, you can instead use:
 
 ```bash

sdks/go/bindings/README.md

@@ -30,7 +30,12 @@ vendor` includes the bindings package.
 Requirements:
 
 - `CGO_ENABLED=1` (default on Linux and macOS)
-- A C compiler (`gcc` on Linux, Xcode CLI tools on macOS, MinGW on Windows)
+- A C compiler (`gcc` on Linux, Xcode CLI tools on macOS)
+- One of the supported native targets: Linux (`amd64`, `arm64`) or Apple Silicon
+  macOS (`arm64`)
+
+Windows currently uses the bindings-unavailable stub. Native Windows support
+will require a MinGW-compatible C SDK release artifact.
 
 ## Layout
 
@@ -44,7 +49,6 @@ bindings/
     linux-amd64/             # libmoss.a (gitignored, downloaded at build time)
     linux-arm64/
     darwin-arm64/
-    windows-amd64/
 ```
 
 Native `.a` / `.lib` files are gitignored. The

sdks/go/bindings/lib/windows-amd64/.gitignore

@@ -1,4 +1,4 @@
-//go:build cgo && ((linux && (amd64 || arm64)) || (darwin && arm64) || (windows && amd64))
+//go:build cgo && ((linux && (amd64 || arm64)) || (darwin && arm64))
 
 package mosscore
 

sdks/go/bindings/libmoss.go

@@ -1,4 +1,4 @@
-//go:build !cgo || !((linux && (amd64 || arm64)) || (darwin && arm64) || (windows && amd64))
+//go:build !cgo || !((linux && (amd64 || arm64)) || (darwin && arm64))
 
 package mosscore
 

sdks/go/bindings/prebuilt_windows_amd64.go

@@ -20,6 +20,8 @@ The Go SDK now has two layers:
 ## Current limitations
 
 - CGO and a C compiler are required for full SDK functionality (`CGO_ENABLED=1`)
+- Native bindings support Linux (`amd64`, `arm64`) and Apple Silicon macOS
+  (`arm64`); unsupported platforms use the bindings-unavailable stub
 - cloud query fallback supports `TopK` and caller-provided embeddings; `Alpha` and `Filter` require a locally loaded index
 - `LoadIndexOptions.CachePath` is not exposed by the current `libmoss` C API yet
 
@@ -31,7 +33,8 @@ go run github.com/usemoss/moss/sdks/go/tools/install@latest --vendor
 ```
 
 The install tool downloads the static `libmoss` library for your platform. See
-[`../bindings/README.md`](../bindings/README.md) for Windows toolchain notes.
+[`../bindings/README.md`](../bindings/README.md) for supported platforms and
+toolchain notes.
 The explicit `--vendor` option vendors the SDK so CGO can link the downloaded
 library from a writable directory; commit `vendor/` if your project commits
 vendored dependencies. Run it after your application imports the SDK so the

sdks/go/bindings/stub.go

@@ -47,10 +47,6 @@ var platforms = []platform{
 		id: "darwin-arm64", triple: "aarch64-apple-darwin",
 		libFile: "libmoss.a", srcLib: "lib/libmoss.a",
 	},
-	{
-		id: "windows-amd64", triple: "x86_64-pc-windows-msvc",
-		libFile: "moss.lib", srcLib: "lib/moss.lib",
-	},
 }
 
 func main() {
@@ -238,8 +234,6 @@ func currentPlatformID() (string, error) {
 		return "linux-arm64", nil
 	case "darwin/arm64":
 		return "darwin-arm64", nil
-	case "windows/amd64":
-		return "windows-amd64", nil
 	default:
 		return "", fmt.Errorf("unsupported platform %s/%s", runtime.GOOS, runtime.GOARCH)
 	}