Introduce hlsl-out-if-target-windows feature to Naga

naga/Cargo.toml

@@ -43,7 +43,18 @@ spv-in = ["dep:petgraph", "dep:spirv"]
 spv-out = ["dep:spirv"]
 wgsl-in = ["dep:hexf-parse", "dep:unicode-xid", "compact"]
 wgsl-out = []
+
+## Enables outputting to HLSL (Microsoft's High-Level Shader Language).
+##
+## This enables HLSL output regardless of the target platform.
+## If you want to enable it only when targeting Windows, use `hlsl-out-if-target-windows`.
 hlsl-out = []
+
+## Enables outputting to HLSL (Microsoft's High-Level Shader Language) only if the target platform is Windows.
+##
+## If you want to enable HLSL output it regardless of the target platform, use `naga/hlsl-out`.
+hlsl-out-if-target-windows = []
+
 compact = []
 
 [dependencies]

naga/build.rs

@@ -2,7 +2,7 @@ fn main() {
     cfg_aliases::cfg_aliases! {
         dot_out: { feature = "dot-out" },
         glsl_out: { feature = "glsl-out" },
-        hlsl_out: { feature = "hlsl-out" },
+        hlsl_out: { any(feature = "hlsl-out", all(target_os = "windows", feature = "hlsl-out-if-target-windows")) },
         msl_out: { any(feature = "msl-out", all(any(target_os = "ios", target_os = "macos"), feature = "msl-out-if-target-apple")) },
         spv_out: { feature = "spv-out" },
         wgsl_out: { feature = "wgsl-out" },

wgpu-hal/Cargo.toml

@@ -63,8 +63,12 @@ gles = [
     "dep:ndk-sys",
     "winapi/libloaderapi",
 ]
+## Enables the DX12 backend when targeting Windows.
+##
+## Has no effect if not targeting Windows.
 dx12 = [
-    "naga/hlsl-out",
+    # DX12 is only available on Windows, therefore request HLSL output also only if we target Windows.
+    "naga/hlsl-out-if-target-windows",
     "dep:d3d12",
     "dep:bit-set",
     "dep:libloading",