Make all backends controlled by features (using a very ugly workaround)

Cargo.toml

@@ -21,6 +21,10 @@ members = [
     "wgpu-macros",
     "wgpu-types",
     "wgpu",
+    "wgpu-core-conditional/arch-wasm",
+    "wgpu-core-conditional/target-unix-non-apple",
+    "wgpu-core-conditional/target-apple",
+    "wgpu-core-conditional/target-windows",
 ]
 exclude = []
 default-members = [
@@ -40,6 +44,10 @@ default-members = [
     "wgpu-macros",
     "wgpu-types",
     "wgpu",
+    "wgpu-core-conditional/arch-wasm",
+    "wgpu-core-conditional/target-unix-non-apple",
+    "wgpu-core-conditional/target-apple",
+    "wgpu-core-conditional/target-windows",
 ]
 
 [workspace.lints.clippy]
@@ -61,11 +69,19 @@ naga = { version = "24.0.0", path = "./naga" }
 wgpu = { version = "24.0.0", path = "./wgpu", default-features = false, features = [
     "serde",
     "wgsl",
+    "static-dxc",
+
+    # Enabled all native non-indirect (not going through additional layers like Angle) backends for testing.
     "dx12",
     "metal",
-    "static-dxc",
+    "vulkan",
+    "gles",
 ] }
 wgpu-core = { version = "24.0.0", path = "./wgpu-core" }
+wgpu-core-if-arch-wasm = { version = "24.0.0", path = "./wgpu-core-conditional/arch-wasm" }
+wgpu-core-if-target-unix-non-apple = { version = "24.0.0", path = "./wgpu-core-conditional/target-unix-non-apple" }
+wgpu-core-if-target-apple = { version = "24.0.0", path = "./wgpu-core-conditional/target-apple" }
+wgpu-core-if-target-windows = { version = "24.0.0", path = "./wgpu-core-conditional/target-windows" }
 wgpu-hal = { version = "24.0.0", path = "./wgpu-hal" }
 wgpu-macros = { version = "24.0.0", path = "./wgpu-macros" }
 wgpu-test = { version = "24.0.0", path = "./tests" }
@@ -167,7 +183,7 @@ glutin_wgl_sys = "0.6"
 # DX12 and GLES dependencies
 windows = { version = "0.58", default-features = false }
 
-# wasm32 dependencies
+# wasm dependencies
 console_error_panic_hook = "0.1.7"
 console_log = "1"
 js-sys = { version = "0.3.70", default-features = false }

wgpu-core-conditional/arch-wasm/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "wgpu-core-if-arch-wasm"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+description = "Workaround crate for enabling in wgpu-core when targeting wasm"
+homepage.workspace = true
+repository.workspace = true
+keywords.workspace = true
+license.workspace = true
+
+[lib]
+
+[features]
+gles = ["wgpu-core/gles"]
+
+[target.'cfg(target_arch = "wasm32")'.dependencies]
+wgpu-core.workspace = true

wgpu-core-conditional/arch-wasm/src/lib.rs

@@ -0,0 +1,4 @@
+//! No code. See README.md for details.
+
+#[cfg(target_arch = "wasm32")]
+pub use wgpu_core::*;

wgpu-core-conditional/target-apple/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "wgpu-core-if-target-apple"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+description = "Workaround crate for enabling wgpu-core when targeting macOS/iOS/tvOS/VisionOS"
+homepage.workspace = true
+repository.workspace = true
+keywords.workspace = true
+license.workspace = true
+
+[lib]
+
+[features]
+gles = ["wgpu-core/gles"]
+metal = ["wgpu-core/metal"]
+vulkan = ["wgpu-core/vulkan"]
+
+raw-window-handle = ["wgpu-core/raw-window-handle"]
+
+[target.'cfg(target_vendor = "apple")'.dependencies]
+wgpu-core.workspace = true

wgpu-core-conditional/target-apple/src/lib.rs

@@ -0,0 +1,4 @@
+//! No code. See README.md for details.
+
+#[cfg(target_vendor = "apple")]
+pub use wgpu_core;

wgpu-core-conditional/target-unix-non-apple/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "wgpu-core-if-target-unix-non-apple"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+description = "Workaround crate for enabling in wgpu-core when targeting native non-apple native unix platforms"
+homepage.workspace = true
+repository.workspace = true
+keywords.workspace = true
+license.workspace = true
+
+[lib]
+
+[features]
+gles = ["wgpu-core/gles"]
+renderdoc = ["wgpu-core/renderdoc"]
+vulkan = ["wgpu-core/vulkan"]
+
+[target.'cfg(all(unix, not(target_os = "emscripten"), not(target_vendor = "apple")))'.dependencies]
+wgpu-core.workspace = true

wgpu-core-conditional/target-unix-non-apple/src/lib.rs

@@ -0,0 +1,4 @@
+//! No code. See README.md for details.
+
+#[cfg(all(unix, not(target_os = "emscripten"), not(target_vendor = "apple")))]
+pub use wgpu_core::*;

wgpu-core-conditional/target-windows/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "wgpu-core-if-target-windows"
+version.workspace = true
+authors.workspace = true
+edition.workspace = true
+description = "Workaround crate for enabling wgpu-core when targeting windows"
+homepage.workspace = true
+repository.workspace = true
+keywords.workspace = true
+license.workspace = true
+
+[lib]
+
+[features]
+dx12 = ["wgpu-core/dx12"]
+gles = ["wgpu-core/gles"]
+vulkan = ["wgpu-core/vulkan"]
+
+[target.'cfg(windows)'.dependencies]
+wgpu-core.workspace = true

wgpu-core-conditional/target-windows/src/lib.rs

@@ -0,0 +1,4 @@
+//! No code. See README.md for details.
+
+#[cfg(windows)]
+pub use wgpu_core::*;

wgpu-core/src/lib.rs

@@ -56,8 +56,8 @@
 // (the only reason to use wgpu-core on the web in the first place) that have atomics enabled.
 #![cfg_attr(not(send_sync), allow(clippy::arc_with_non_send_sync))]
 
-extern crate wgpu_hal as hal;
-extern crate wgpu_types as wgt;
+pub extern crate wgpu_hal as hal;
+pub extern crate wgpu_types as wgt;
 
 pub mod binding_model;
 pub mod command;

wgpu-types/Cargo.toml

@@ -40,12 +40,12 @@ default = ["std"]
 std = ["js-sys/std", "web-sys/std"]
 strict_asserts = []
 fragile-send-sync-non-atomic-wasm = []
-serde = ["dep:serde"]
+serde = ["dep:serde", "bitflags/serde"]
 # Enables some internal instrumentation for debugging purposes.
 counters = []
 
 [dependencies]
-bitflags = { workspace = true, features = ["serde"] }
+bitflags.workspace = true
 log.workspace = true
 serde = { workspace = true, default-features = false, features = [
     "alloc",

wgpu/Cargo.toml

@@ -28,33 +28,48 @@ ignored = ["cfg_aliases"]
 [lib]
 
 [features]
-default = ["wgsl", "dx12", "metal", "webgpu"]
+default = ["wgsl", "dx12", "metal", "vulkan", "gles", "webgpu"]
 
 #! ### Backends
 # --------------------------------------------------------------------
-#! ⚠️ WIP: Not all backends can be manually configured today.
-#! On Windows, Linux & Android the Vulkan & GLES backends are always enabled.
-#! See [#3514](https://github.com/gfx-rs/wgpu/issues/3514) for more details.
 
 ## Enables the DX12 backend on Windows.
-dx12 = ["wgpu-core?/dx12"]
+# Note that while wgpu-hal ignores dx12 for non-windows targets, we still need to use a proxy crate,
+# since for non-windows targets we don't want to include wgpu-core in the first place via this feature.
+dx12 = ["wgpu-core-if-target-windows/dx12"]
 
 ## Enables the Metal backend on macOS & iOS.
-metal = ["wgpu-core?/metal"]
+# Note that while wgpu-hal ignores metal for non-apple targets, we still need to use a proxy crate,
+# since for non-apple targets we don't want to include wgpu-core in the first place via this feature.
+metal = ["wgpu-core-if-target-apple/metal"]
 
-## Enables the WebGPU backend on Wasm. Disabled when targeting `emscripten`.
-webgpu = ["naga?/wgsl-out"]
-
-## Enables the GLES backend via [ANGLE](https://github.com/google/angle) on macOS using.
-angle = ["wgpu-core?/gles"]
+## Enables the Vulkan backend on Windows, Linux, and Android.
+##
+## For enabling Vulkan on macOS & iOS, use the `vulkan-portability` feature.
+vulkan = [
+    "wgpu-core-if-target-unix-non-apple/vulkan",
+    "wgpu-core-if-target-windows/vulkan",
+]
 
 ## Enables the Vulkan backend on macOS & iOS.
-vulkan-portability = ["wgpu-core?/vulkan"]
+vulkan-portability = ["wgpu-core-if-target-apple/vulkan"]
 
-## Enables the GLES backend on Wasm
+## Enables the OpenGL/GLES backend on Windows, Linux, and Android.
 ##
-## * ⚠️ WIP: Currently will also enable GLES dependencies on any other targets.
-webgl = ["dep:wgpu-hal", "wgpu-core/gles"]
+## For enabling WebGL use the `webgl` feature, for enabling OpenGL via ANGLE on macOS use the `angle` feature.
+gles = [
+    "wgpu-core-if-target-unix-non-apple/gles",
+    "wgpu-core-if-target-windows/gles",
+]
+
+## Enables the GLES backend via [ANGLE](https://github.com/google/angle) on macOS using.
+angle = ["wgpu-core-if-target-apple/gles"]
+
+## Enables GLES backend (WebGL) on Wasm
+webgl = ["wgpu-core-if-arch-wasm/gles"]
+
+## Enables the WebGPU backend on Wasm. Disabled when targeting `emscripten`.
+webgpu = ["naga?/wgsl-out"]
 
 #! **Note:** In the documentation, if you see that an item depends on a backend,
 #! it means that the item is only available when that backend is enabled _and_ the backend
@@ -84,23 +99,23 @@ naga-ir = ["dep:naga"]
 strict_asserts = ["wgpu-core?/strict_asserts", "wgpu-types/strict_asserts"]
 
 ## Enables serialization via `serde` on common wgpu types.
-serde = ["dep:serde", "wgpu-core/serde"]
+serde = ["dep:serde", "wgpu-core?/serde", "wgpu-types/serde"]
 
 # Uncomment once we get to https://github.com/gfx-rs/wgpu/issues/5974
 # ## Allow writing of trace capture files. See [`Adapter::request_device`].
 # trace = ["serde", "wgpu-core/trace"]
 
 ## Allow deserializing of trace capture files that were written with the `trace` feature.
 ## To replay a trace file use the [wgpu player](https://github.com/gfx-rs/wgpu/tree/trunk/player).
-replay = ["serde", "wgpu-core/replay"]
+replay = ["serde", "wgpu-core?/replay"]
 
 #! ### Other
 # --------------------------------------------------------------------
 
 ## Internally count resources and events for debugging purposes. If the counters
 ## feature is disabled, the counting infrastructure is removed from the build and
 ## the exposed counters always return 0.
-counters = ["wgpu-core/counters"]
+counters = ["wgpu-core?/counters"]
 
 ## Implement `Send` and `Sync` on Wasm, but only if atomics are not enabled.
 ##
@@ -111,8 +126,8 @@ counters = ["wgpu-core/counters"]
 ## but on a wasm binary compiled without atomics we know we are definitely
 ## not in a multithreaded environment.
 fragile-send-sync-non-atomic-wasm = [
-    "wgpu-hal/fragile-send-sync-non-atomic-wasm",
-    "wgpu-core/fragile-send-sync-non-atomic-wasm",
+    "wgpu-hal?/fragile-send-sync-non-atomic-wasm",
+    "wgpu-core?/fragile-send-sync-non-atomic-wasm",
     "wgpu-types/fragile-send-sync-non-atomic-wasm",
 ]
 
@@ -134,8 +149,11 @@ static-dxc = ["wgpu-hal/static-dxc"]
 
 [dependencies]
 naga = { workspace = true, optional = true }
-wgpu-core = { workspace = true, optional = true }
-wgpu-types = { workspace = true, features = ["serde"] }
+wgpu-core = { workspace = true, optional = true, features = [
+    "raw-window-handle",
+] }
+wgpu-types = { workspace = true }
+wgpu-hal = { workspace = true, optional = true, features = ["renderdoc"] }
 
 arrayvec.workspace = true
 bitflags.workspace = true
@@ -148,40 +166,17 @@ serde = { workspace = true, features = ["default", "derive"], optional = true }
 smallvec.workspace = true
 static_assertions.workspace = true
 
+wgpu-core-if-arch-wasm = { workspace = true, optional = true }
+wgpu-core-if-target-unix-non-apple = { workspace = true, optional = true }
+wgpu-core-if-target-apple = { workspace = true, optional = true }
+wgpu-core-if-target-windows = { workspace = true, optional = true }
+
+
 ########################################
 # Target Specific Feature Dependencies #
 ########################################
-
-# Windows
-[target.'cfg(windows)'.dependencies]
-wgpu-core = { workspace = true, features = [
-    "raw-window-handle",
-    "vulkan",
-    "gles",
-] }
-wgpu-hal = { workspace = true, features = ["renderdoc"] }
-
-# Apple Platforms
-[target.'cfg(target_vendor = "apple")'.dependencies]
-wgpu-core = { workspace = true, features = ["raw-window-handle"] }
-wgpu-hal = { workspace = true, features = [] }
-
-# Linux + Android
-[target.'cfg(any(target_os = "linux", target_os = "android"))'.dependencies]
-wgpu-core = { workspace = true, features = [
-    "raw-window-handle",
-    "vulkan",
-    "gles",
-] }
-wgpu-hal = { workspace = true, features = ["renderdoc"] }
-
 # Webassembly
 [target.'cfg(all(target_arch = "wasm32", not(target_os = "emscripten")))'.dependencies]
-wgpu-core = { workspace = true, optional = true, features = [
-    "raw-window-handle",
-] }
-wgpu-hal = { workspace = true, optional = true }
-
 js-sys = { workspace = true, features = ["default"] }
 parking_lot.workspace = true
 wasm-bindgen-futures.workspace = true