[BREAKING] Make Shader(Module)Source::Wgsl optional (#2890)

Author: daxpedda

.github/workflows/ci.yml

@@ -178,6 +178,9 @@ jobs:
       - name: check web
         if: matrix.kind == 'web'
         run: |
+          # build with no features
+          cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu --no-default-features
+
           # build examples
           cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu --examples
 
@@ -194,7 +197,7 @@ jobs:
         if: matrix.kind == 'em'
         run: |
           # build for Emscripten/WebGL
-          cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu -p wgpu-hal --features webgl,emscripten
+          cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu -p wgpu-hal --no-default-features --features webgl,emscripten
 
           # build raw-gles example
           cargo ${{matrix.tool}} --target ${{ matrix.target }} --example raw-gles --features webgl,emscripten
@@ -203,7 +206,7 @@ jobs:
         if: matrix.kind == 'local' || matrix.kind == 'other'
         run: |
           # check with no features
-          cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu -p wgpu-core -p wgpu-info -p player
+          cargo ${{matrix.tool}} --target ${{ matrix.target }} -p wgpu -p wgpu-core -p wgpu-info -p player --no-default-features
 
           # check with all features
           # explicitly don't mention wgpu-hal so that --all-features don't apply to it

CHANGELOG.md

@@ -47,6 +47,10 @@ Bottom level categories:
 - Convert all `Default` Implementations on Enums to `derive(Default)`
 - Implement `Default` for `CompositeAlphaMode`
 
+### Added/New Features
+
+Add the `"wgsl"` feature, to enable WGSL shaders in `wgpu-core` and `wgpu`. Enabled by default in `wgpu`. By @daxpedda in [#2890](https://github.com/gfx-rs/wgpu/pull/2890).
+
 ### Bug Fixes
 
 #### General

deno_webgpu/Cargo.toml

@@ -14,5 +14,5 @@ description = "WebGPU implementation for Deno"
 deno_core = "0.151.0"
 serde = { version = "1.0", features = ["derive"] }
 tokio = { version = "1.19", features = ["full"] }
-wgpu-core = { path = "../wgpu-core", features = ["trace", "replay", "serde", "strict_asserts"] }
+wgpu-core = { path = "../wgpu-core", features = ["trace", "replay", "serde", "strict_asserts", "wgsl"] }
 wgpu-types = { path = "../wgpu-types", features = ["trace", "replay", "serde"] }

player/Cargo.toml

@@ -29,7 +29,7 @@ features = ["replay"]
 [dependencies.wgc]
 path = "../wgpu-core"
 package = "wgpu-core"
-features = ["replay", "raw-window-handle", "strict_asserts"]
+features = ["replay", "raw-window-handle", "strict_asserts", "wgsl"]
 
 [dev-dependencies]
 serde = "1"

wgpu-core/Cargo.toml

@@ -24,6 +24,8 @@ replay = ["serde", "wgt/replay", "arrayvec/serde", "naga/deserialize"]
 # Enable serializable compute/render passes, and bundle encoders.
 serial-pass = ["serde", "wgt/serde", "arrayvec/serde"]
 id32 = []
+# Enable `ShaderModuleSource::Wgsl`
+wgsl = ["naga/wgsl-in"]
 vulkan-portability = ["hal/vulkan"]
 
 [dependencies]
@@ -46,7 +48,7 @@ thiserror = "1"
 git = "https://github.com/gfx-rs/naga"
 rev = "c52d9102"
 version = "0.10"
-features = ["clone", "span", "validate", "wgsl-in"]
+features = ["clone", "span", "validate"]
 
 [dependencies.wgt]
 path = "../wgpu-types"

wgpu-core/src/device/mod.rs

@@ -1203,6 +1203,7 @@ impl<A: HalApi> Device<A> {
         source: pipeline::ShaderModuleSource<'a>,
     ) -> Result<pipeline::ShaderModule<A>, pipeline::CreateShaderModuleError> {
         let (module, source) = match source {
+            #[cfg(feature = "wgsl")]
             pipeline::ShaderModuleSource::Wgsl(code) => {
                 profiling::scope!("naga::wgsl::parse_str");
                 let module = naga::front::wgsl::parse_str(&code).map_err(|inner| {
@@ -1215,6 +1216,7 @@ impl<A: HalApi> Device<A> {
                 (Cow::Owned(module), code.into_owned())
             }
             pipeline::ShaderModuleSource::Naga(module) => (module, String::new()),
+            pipeline::ShaderModuleSource::Dummy(_) => panic!("found `ShaderModuleSource::Dummy`"),
         };
         for (_, var) in module.global_variables.iter() {
             match var.binding {
@@ -4397,6 +4399,7 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
             if let Some(ref trace) = device.trace {
                 let mut trace = trace.lock();
                 let data = match source {
+                    #[cfg(feature = "wgsl")]
                     pipeline::ShaderModuleSource::Wgsl(ref code) => {
                         trace.make_binary("wgsl", code.as_bytes())
                     }
@@ -4406,6 +4409,9 @@ impl<G: GlobalIdentityHandlerFactory> Global<G> {
                                 .unwrap();
                         trace.make_binary("ron", string.as_bytes())
                     }
+                    pipeline::ShaderModuleSource::Dummy(_) => {
+                        panic!("found `ShaderModuleSource::Dummy`")
+                    }
                 };
                 trace.add(trace::Action::CreateShaderModule {
                     id: fid.id(),

wgpu-core/src/pipeline.rs

@@ -6,7 +6,7 @@ use crate::{
     validation, Label, LifeGuard, Stored,
 };
 use arrayvec::ArrayVec;
-use std::{borrow::Cow, error::Error, fmt, num::NonZeroU32};
+use std::{borrow::Cow, error::Error, fmt, marker::PhantomData, num::NonZeroU32};
 use thiserror::Error;
 
 /// Information about buffer bindings, which
@@ -20,8 +20,13 @@ pub(crate) struct LateSizedBufferGroup {
 
 #[allow(clippy::large_enum_variant)]
 pub enum ShaderModuleSource<'a> {
+    #[cfg(feature = "wgsl")]
     Wgsl(Cow<'a, str>),
     Naga(Cow<'static, naga::Module>),
+    /// Dummy variant because `Naga` doesn't have a lifetime and without enough active features it
+    /// could be the last one active.
+    #[doc(hidden)]
+    Dummy(PhantomData<&'a ()>),
 }
 
 #[derive(Clone, Debug)]
@@ -63,6 +68,7 @@ pub struct ShaderError<E> {
     pub label: Option<String>,
     pub inner: E,
 }
+#[cfg(feature = "wgsl")]
 impl fmt::Display for ShaderError<naga::front::wgsl::ParseError> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let label = self.label.as_deref().unwrap_or_default();
@@ -114,6 +120,7 @@ where
 //Note: `Clone` would require `WithSpan: Clone`.
 #[derive(Debug, Error)]
 pub enum CreateShaderModuleError {
+    #[cfg(feature = "wgsl")]
     #[error(transparent)]
     Parsing(#[from] ShaderError<naga::front::wgsl::ParseError>),
     #[error("Failed to generate the backend-specific code")]
@@ -137,6 +144,7 @@ pub enum CreateShaderModuleError {
 impl CreateShaderModuleError {
     pub fn location(&self, source: &str) -> Option<naga::SourceLocation> {
         match *self {
+            #[cfg(feature = "wgsl")]
             CreateShaderModuleError::Parsing(ref err) => err.inner.location(source),
             CreateShaderModuleError::Validation(ref err) => err.inner.location(source),
             _ => None,

wgpu-hal/Cargo.toml

@@ -8,7 +8,7 @@ homepage = "https://github.com/gfx-rs/wgpu"
 repository = "https://github.com/gfx-rs/wgpu"
 keywords = ["graphics"]
 license = "MIT OR Apache-2.0"
-rust-version = "1.59"
+rust-version = "1.60"
 
 [lib]
 

wgpu/Cargo.toml

@@ -76,9 +76,10 @@ name = "water"
 test = true
 
 [features]
-default = []
+default = ["wgsl"]
 spirv = ["naga/spv-in"]
 glsl = ["naga/glsl-in"]
+wgsl = ["wgc?/wgsl"]
 trace = ["serde", "wgc/trace"]
 replay = ["serde", "wgc/replay"]
 angle = ["wgc/angle"]

wgpu/src/backend/direct.rs

@@ -1094,6 +1094,15 @@ impl crate::Context for Context {
         }
     }
 
+    #[cfg_attr(
+        not(any(
+            feature = "spirv",
+            feature = "glsl",
+            feature = "wgsl",
+            feature = "naga"
+        )),
+        allow(unreachable_code, unused_variables)
+    )]
     fn device_create_shader_module(
         &self,
         device: &Self::DeviceId,
@@ -1134,9 +1143,11 @@ impl crate::Context for Context {
 
                 wgc::pipeline::ShaderModuleSource::Naga(std::borrow::Cow::Owned(module))
             }
+            #[cfg(feature = "wgsl")]
             ShaderSource::Wgsl(ref code) => wgc::pipeline::ShaderModuleSource::Wgsl(Borrowed(code)),
             #[cfg(feature = "naga")]
             ShaderSource::Naga(module) => wgc::pipeline::ShaderModuleSource::Naga(module),
+            ShaderSource::Dummy(_) => panic!("found `ShaderSource::Dummy`"),
         };
         let (id, error) = wgc::gfx_select!(
             device.id => global.device_create_shader_module(device.id, &descriptor, source, ())