Fix building wgpu with --no-default-feautures on web (`wasm32-unk…

…nown-unknown`) (#6946)

* Fix wasm build without features

* silence unused warnings if wgc & webgpu are disabled

* add no-features check for web ci

* add changelog entry

.github/workflows/ci.yml

@@ -254,6 +254,9 @@ jobs:
           cargo clippy --target ${{ matrix.target }} ${{ matrix.extra-flags }} --tests --features glsl,spirv
           cargo doc --target ${{ matrix.target }} ${{ matrix.extra-flags }} --no-deps --features glsl,spirv
 
+          # check with no features
+          cargo clippy --target ${{ matrix.target }} ${{ matrix.extra-flags }} --no-default-features
+
           # all features
           cargo clippy --target ${{ matrix.target }} ${{ matrix.extra-flags }} --tests --all-features
           cargo doc --target ${{ matrix.target }} ${{ matrix.extra-flags }} --no-deps --all-features

CHANGELOG.md

@@ -63,6 +63,7 @@ By @brodycj in [#6925](https://github.com/gfx-rs/wgpu/pull/6925).
 ### Bug Fixes
 
 * Avoid overflow in query set bounds check validation. By @ErichDonGubler in [#????].
+* Fix `wgpu` not building with `--no-default-features` on when targeting `wasm32-unknown-unknown`. By @wumpf in [#6946](https://github.com/gfx-rs/wgpu/pull/6946).
 
 ## v24.0.0 (2025-01-15)
 

wgpu/src/dispatch.rs

@@ -636,6 +636,8 @@ macro_rules! dispatch_types_inner {
                     Self::Core(value) => value.as_ref(),
                     #[cfg(webgpu)]
                     Self::WebGPU(value) => value.as_ref(),
+                    #[cfg(not(any(wgpu_core, webgpu)))]
+                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
                 }
             }
         }
@@ -765,6 +767,8 @@ macro_rules! dispatch_types_inner {
                     Self::Core(value) => value,
                     #[cfg(webgpu)]
                     Self::WebGPU(value) => value,
+                    #[cfg(not(any(wgpu_core, webgpu)))]
+                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
                 }
             }
         }
@@ -777,6 +781,8 @@ macro_rules! dispatch_types_inner {
                     Self::Core(value) => value,
                     #[cfg(webgpu)]
                     Self::WebGPU(value) => value,
+                    #[cfg(not(any(wgpu_core, webgpu)))]
+                    _ => panic!("No context available. You need to enable one of wgpu's backend feature build flags."),
                 }
             }
         }

wgpu/src/lib.rs

@@ -23,6 +23,7 @@
     unsafe_op_in_unsafe_fn
 )]
 #![allow(clippy::arc_with_non_send_sync)]
+#![cfg_attr(not(any(wgpu_core, webgpu)), allow(unused))]
 
 //
 //