| # Copyright 2018 The Dawn Authors | 
 | # | 
 | # Licensed under the Apache License, Version 2.0 (the "License"); | 
 | # you may not use this file except in compliance with the License. | 
 | # You may obtain a copy of the License at | 
 | # | 
 | #     http://www.apache.org/licenses/LICENSE-2.0 | 
 | # | 
 | # Unless required by applicable law or agreed to in writing, software | 
 | # distributed under the License is distributed on an "AS IS" BASIS, | 
 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
 | # See the License for the specific language governing permissions and | 
 | # limitations under the License. | 
 |  | 
 | import("//build_overrides/build.gni") | 
 |  | 
 | if (build_with_chromium) { | 
 |   import("//build/config/ozone.gni") | 
 |   import("//build/config/sanitizers/sanitizers.gni") | 
 |  | 
 |   dawn_use_x11 = ozone_platform_x11 | 
 |   dawn_use_wayland = false | 
 | } else { | 
 |   declare_args() { | 
 |     # Whether Dawn should enable X11 support. | 
 |     dawn_use_x11 = is_linux && !is_chromeos | 
 |     dawn_use_wayland = false | 
 |   } | 
 | } | 
 |  | 
 | # Enable the compilation for UWP | 
 | dawn_is_winuwp = is_win && target_os == "winuwp" | 
 |  | 
 | declare_args() { | 
 |   # TODO(dawn:1545): Re-enable dawn_use_angle on Android. In non-component | 
 |   # builds, this is adding a dependency on ANGLE's libEGL.so and | 
 |   # libGLESv2.so, apparently without regard for the use_static_angle=true | 
 |   # GN variable. Chromium's linker on Android disallows production of more | 
 |   # than one shared object per target (?). | 
 |   dawn_use_angle = !is_android | 
 |  | 
 |   # Enables SwiftShader as the fallback adapter. Requires dawn_swiftshader_dir | 
 |   # to be set to take effect. | 
 |   # TODO(dawn:1536): Enable SwiftShader for Android. | 
 |   dawn_use_swiftshader = !is_android | 
 | } | 
 |  | 
 | declare_args() { | 
 |   # Enable Dawn's ASSERTs even in release builds | 
 |   dawn_always_assert = false | 
 |  | 
 |   # Should the Dawn static libraries be fully linked vs. GN's default of | 
 |   # treating them as source sets. This is useful for people using Dawn | 
 |   # standalone to produce static libraries to use in their projects. | 
 |   dawn_complete_static_libs = false | 
 |  | 
 |   # Enables the compilation of Dawn's D3D12 backend | 
 |   dawn_enable_d3d12 = is_win | 
 |  | 
 |   # Enables the compilation of Dawn's Metal backend | 
 |   dawn_enable_metal = is_mac | 
 |  | 
 |   # Enables the compilation of Dawn's Null backend | 
 |   # (required for unittests, obviously non-conformant) | 
 |   dawn_enable_null = true | 
 |  | 
 |   # Enables the compilation of Dawn's OpenGL backend | 
 |   # (best effort, non-conformant) | 
 |   dawn_enable_desktop_gl = is_linux && !is_chromeos | 
 |  | 
 |   # Enables the compilation of Dawn's OpenGLES backend | 
 |   # (WebGPU/Compat subset) | 
 |   # Disables OpenGLES when compiling for UWP, since UWP only supports d3d | 
 |   dawn_enable_opengles = | 
 |       (is_linux && !is_chromeos) || (is_win && !dawn_is_winuwp) | 
 |  | 
 |   # Enables the compilation of Dawn's Vulkan backend | 
 |   # Disables vulkan when compiling for UWP, since UWP only supports d3d | 
 |   dawn_enable_vulkan = is_linux || is_chromeos || (is_win && !dawn_is_winuwp) || | 
 |                        is_fuchsia || is_android || dawn_use_swiftshader | 
 |  | 
 |   # Enables error injection for faking failures to native API calls | 
 |   dawn_enable_error_injection = | 
 |       is_debug || (build_with_chromium && use_fuzzing_engine) | 
 | } | 
 |  | 
 | # GN does not allow reading a variable defined in the same declare_args(). | 
 | # Put them in two separate declare_args() when setting the value of one | 
 | # argument based on another. | 
 | declare_args() { | 
 |   # Uses our built version of the Vulkan validation layers | 
 |   dawn_enable_vulkan_validation_layers = | 
 |       dawn_enable_vulkan && ((is_linux && !is_chromeos) || is_win || is_mac) | 
 |  | 
 |   # Uses our built version of the Vulkan loader on platforms where we can't | 
 |   # assume to have one present at the system level. | 
 |   dawn_enable_vulkan_loader = | 
 |       dawn_enable_vulkan && (is_mac || (is_linux && !is_android)) | 
 |  | 
 |   # Disable SPIR-V validation on Android because it adds a significant amount | 
 |   # to the binary size, and Tint's output should be well-formed. | 
 |   dawn_enable_spirv_validation = dawn_enable_vulkan && !is_android | 
 | } | 
 |  | 
 | # UWP only supports CoreWindow for windowing | 
 | dawn_supports_glfw_for_windowing = | 
 |     (is_win && !dawn_is_winuwp) || (is_linux && !is_chromeos) || is_mac | 
 |  | 
 | # Much of the GL backend code is shared, so define a convenience var. | 
 | dawn_enable_opengl = dawn_enable_opengles || dawn_enable_desktop_gl |