gpu: make all next_in_chain fields optional, default to null

Signed-off-by: Stephen Gutekanst <stephen@hexops.com>

gpu/src/adapter.zig

@@ -66,7 +66,7 @@ pub const AdapterType = enum(u32) {
 };
 
 pub const AdapterProperties = extern struct {
-    next_in_chain: *ChainedStructOut,
+    next_in_chain: ?*ChainedStructOut = null,
     vendor_id: u32,
     vendor_name: [*:0]const u8,
     architecture: [*:0]const u8,

gpu/src/bind_group.zig

@@ -20,7 +20,7 @@ pub const BindGroup = *opaque {
 };
 
 pub const BindGroupEntry = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     binding: u32,
     buffer: ?Buffer,
     offset: u64 = 0,
@@ -30,7 +30,7 @@ pub const BindGroupEntry = extern struct {
 };
 
 pub const BindGroupDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     layout: BindGroupLayout,
     entry_count: u32,

gpu/src/bind_group_layout.zig

@@ -24,7 +24,7 @@ pub const BindGroupLayout = *opaque {
 };
 
 pub const BindGroupLayoutEntry = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     binding: u32,
     visibility: ShaderStageFlags,
     buffer: BufferBindingLayout,
@@ -34,7 +34,7 @@ pub const BindGroupLayoutEntry = extern struct {
 };
 
 pub const BindGroupLayoutDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     entry_count: u32,
     // TODO: file a bug on Dawn, this is not marked as nullable but in fact is.

gpu/src/buffer.zig

@@ -96,14 +96,14 @@ pub const BufferUsage = packed struct {
 };
 
 pub const BufferBindingLayout = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     type: BufferBindingType = .undef,
     has_dynamic_offset: bool = false,
     min_binding_size: u64 = 0,
 };
 
 pub const BufferDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     usage: BufferUsage,
     size: u64,

gpu/src/command_buffer.zig

@@ -16,6 +16,6 @@ pub const CommandBuffer = *opaque {
 };
 
 pub const CommandBufferDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };

gpu/src/command_encoder.zig

@@ -95,6 +95,6 @@ pub const CommandEncoder = *opaque {
 };
 
 pub const CommandEncoderDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };

gpu/src/compute_pipeline.zig

@@ -23,7 +23,7 @@ pub const ComputePipeline = *opaque {
 };
 
 pub const ComputePipelineDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     layout: ?PipelineLayout,
     compute: ProgrammableStageDescriptor,

gpu/src/device.zig

@@ -191,7 +191,7 @@ pub const DeviceLostReason = enum(u32) {
 };
 
 pub const DeviceDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     required_features_count: u32 = 0,
     required_features: ?[*]const FeatureName = null,

gpu/src/external_texture.zig

@@ -30,7 +30,7 @@ pub const ExternalTextureBindingLayout = extern struct {
 };
 
 pub const ExternalTextureDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     plane0: TextureView,
     plane1: ?TextureView,

gpu/src/instance.zig

@@ -32,5 +32,5 @@ pub const RequestAdapterCallback = fn (
 ) callconv(.C) void;
 
 pub const InstanceDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
 };

gpu/src/pipeline_layout.zig

@@ -17,7 +17,7 @@ pub const PipelineLayout = *opaque {
 };
 
 pub const PipelineLayoutDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     bind_group_layout_count: u32,
     // TODO: file a bug on Dawn, this is not marked as nullable but in fact is.

gpu/src/query_set.zig

@@ -30,7 +30,7 @@ pub const QuerySet = *opaque {
 };
 
 pub const QuerySetDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     type: QueryType,
     count: u32,

gpu/src/queue.zig

@@ -54,6 +54,6 @@ pub const QueueWorkDoneStatus = enum(u32) {
 };
 
 pub const QueueDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };

gpu/src/render_bundle.zig

@@ -12,6 +12,6 @@ pub const RenderBundle = *opaque {
 };
 
 pub const RenderBundleDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };

gpu/src/render_bundle_encoder.zig

@@ -84,7 +84,7 @@ pub const RenderBundleEncoder = *opaque {
 };
 
 pub const RenderBundleEncoderDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     color_formats_count: u32,
     // TODO: file a bug on Dawn, this is not marked as nullable but in fact is.

gpu/src/render_pipeline.zig

@@ -27,7 +27,7 @@ pub const RenderPipeline = *opaque {
 };
 
 pub const RenderPipelineDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     layout: ?PipelineLayout,
     vertex: VertexState,

gpu/src/sampler.zig

@@ -31,12 +31,12 @@ pub const SamplerBindingType = enum(u32) {
 };
 
 pub const SamplerBindingLayout = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     type: SamplerBindingType = .undef,
 };
 
 pub const SamplerDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     address_mode_u: SamplerAddressMode = .clamp_to_edge,
     address_mode_v: SamplerAddressMode = .clamp_to_edge,

gpu/src/shader_module.zig

@@ -21,7 +21,7 @@ pub const ShaderModule = *opaque {
 };
 
 pub const ShaderModuleDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };
 

gpu/src/surface.zig

@@ -12,7 +12,7 @@ pub const Surface = *opaque {
 };
 
 pub const SurfaceDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
 };
 

gpu/src/swap_chain.zig

@@ -29,7 +29,7 @@ pub const SwapChain = *opaque {
 };
 
 pub const SwapChainDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     usage: TextureUsageFlags,
     format: TextureFormat,

gpu/src/texture.zig

@@ -215,21 +215,21 @@ pub const TextureUsageFlags = packed struct {
 };
 
 pub const TextureBindingLayout = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     sample_type: TextureSampleType = .undef,
     view_dimension: TextureViewDimension = .dimension_undef,
     multisampled: bool = false,
 };
 
 pub const TextureDataLayout = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     offset: u64 = 0,
     bytes_per_row: u32 = copy_stride_undefined,
     rows_per_image: u32 = copy_stride_undefined,
 };
 
 pub const TextureDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     usage: TextureUsageFlags,
     dimension: TextureDimension = .dimension_2d,

gpu/src/texture_view.zig

@@ -31,7 +31,7 @@ pub const TextureViewDimension = enum(u32) {
 };
 
 pub const TextureViewDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     label: ?[*:0]const u8 = null,
     format: TextureFormat = .undef,
     dimension: TextureViewDimension = .dimension_undef,

gpu/src/types.zig

@@ -460,7 +460,7 @@ pub const Origin3D = extern struct {
 };
 
 pub const CompilationMessage = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     message: ?[*:0]const u8,
     type: CompilationMessageType,
     line_num: u64,
@@ -470,13 +470,13 @@ pub const CompilationMessage = extern struct {
 };
 
 pub const ConstantEntry = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     key: [*:0]const u8,
     value: f64,
 };
 
 pub const CopyTextureForBrowserOptions = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     flip_y: bool = false,
     needs_color_space_conversion: bool = false,
     src_alpha_mode: AlphaMode = .unpremultiplied,
@@ -490,7 +490,7 @@ pub const CopyTextureForBrowserOptions = extern struct {
 };
 
 pub const MultisampleState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     count: u32 = 1,
     mask: u32 = 0xFFFFFFFF,
     alpha_to_coverage_enabled: bool = false,
@@ -507,7 +507,7 @@ pub const PrimitiveDepthClipControl = extern struct {
 };
 
 pub const PrimitiveState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     topology: PrimitiveTopology = .triangle_list,
     strip_index_format: IndexFormat = .undef,
     front_face: FrontFace = .ccw,
@@ -527,7 +527,7 @@ pub const StencilFaceState = extern struct {
 };
 
 pub const StorageTextureBindingLayout = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     access: StorageTextureAccess = .undef,
     format: TextureFormat = .undef,
     view_dimension: TextureViewDimension = .dimension_undef,
@@ -545,14 +545,14 @@ pub const BlendState = extern struct {
 };
 
 pub const CompilationInfo = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     message_count: u32,
     // TODO: file a bug on Dawn, this is not marked as nullable but in fact is.
     messages: ?[*]const CompilationMessage,
 };
 
 pub const DepthStencilState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     format: TextureFormat,
     depth_write_enabled: bool = false,
     depth_compare: CompareFunction = .always,
@@ -566,13 +566,13 @@ pub const DepthStencilState = extern struct {
 };
 
 pub const ImageCopyBuffer = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     layout: TextureDataLayout,
     buffer: Buffer,
 };
 
 pub const ImageCopyTexture = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     texture: Texture,
     mip_level: u32 = 0,
     origin: Origin3D,
@@ -580,7 +580,7 @@ pub const ImageCopyTexture = extern struct {
 };
 
 pub const ProgrammableStageDescriptor = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     module: ShaderModule,
     entry_point: [*:0]const u8,
     constant_count: u32 = 0,
@@ -604,12 +604,12 @@ pub const RenderPassColorAttachment = extern struct {
 };
 
 pub const RequiredLimits = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     limits: Limits,
 };
 
 pub const SupportedLimits = extern struct {
-    next_in_chain: *ChainedStructOut,
+    next_in_chain: ?*ChainedStructOut = null,
     limits: Limits,
 };
 
@@ -622,14 +622,14 @@ pub const VertexBufferLayout = extern struct {
 };
 
 pub const ColorTargetState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     format: TextureFormat,
     blend: ?*const BlendState,
     write_mask: ColorWriteMaskFlags = ColorWriteMaskFlags.all,
 };
 
 pub const VertexState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     module: ShaderModule,
     entry_point: [*:0]const u8,
     constant_count: u32 = 0,
@@ -641,7 +641,7 @@ pub const VertexState = extern struct {
 };
 
 pub const FragmentState = extern struct {
-    next_in_chain: *const ChainedStruct,
+    next_in_chain: ?*const ChainedStruct = null,
     module: ShaderModule,
     entry_point: [*:0]const u8,
     constant_count: u32 = 0,