Add a snapshot of flutter/engine/src/build to our sdk

build/config/BUILDCONFIG.gn

Index: build/config/BUILDCONFIG.gn
diff --git a/build/config/BUILDCONFIG.gn b/build/config/BUILDCONFIG.gn
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+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# =============================================================================
+# PLATFORM SELECTION
+# =============================================================================
+#
+# There are two main things to set: "os" and "cpu". The "toolchain" is the name
+# of the GN thing that encodes combinations of these things.
+#
+# Users typically only set the variables "target_os" and "target_cpu" in "gn
+# args", the rest are set up by our build and internal to GN.
+#
+# There are three different types of each of these things: The "host"
+# represents the computer doing the compile and never changes. The "target"
+# represents the main thing we're trying to build. The "current" represents
+# which configuration is currently being defined, which can be either the
+# host, the target, or something completely different (like nacl). GN will
+# run the same build file multiple times for the different required
+# configuration in the same build.
+#
+# This gives the following variables:
+#  - host_os, host_cpu, host_toolchain
+#  - target_os, target_cpu, default_toolchain
+#  - current_os, current_cpu, current_toolchain.
+#
+# Note the default_toolchain isn't symmetrical (you would expect
+# target_toolchain). This is because the "default" toolchain is a GN built-in
+# concept, and "target" is something our build sets up that's symmetrical with
+# its GYP counterpart. Potentially the built-in default_toolchain variable
+# could be renamed in the future.
+#
+# When writing build files, to do something only for the host:
+#   if (current_toolchain == host_toolchain) { ...
+
+if (target_os == "") {
+  target_os = host_os
+}
+
+if (target_cpu == "") {
+  if (target_os == "android") {
+    # If we're building for Android, we should assume that we want to
+    # build for ARM by default, not the host_cpu (which is likely x64).
+    # This allows us to not have to specify both target_os and target_cpu
+    # on the command line.
+    target_cpu = "arm"
+  } else {
+    target_cpu = host_cpu
+  }
+}
+
+if (current_cpu == "") {
+  current_cpu = target_cpu
+}
+if (current_os == "") {
+  current_os = target_os
+}
+
+# =============================================================================
+# BUILD FLAGS
+# =============================================================================
+#
+# This block lists input arguments to the build, along with their default
+# values.
+#
+# If a value is specified on the command line, it will overwrite the defaults
+# given in a declare_args block, otherwise the default will be used.
+#
+# YOU SHOULD ALMOST NEVER NEED TO ADD FLAGS TO THIS FILE. GN allows any file in
+# the build to declare build flags. If you need a flag for a single component,
+# you can just declare it in the corresponding BUILD.gn file. If you need a
+# flag in multiple components, there are a few options:
+#
+# - If your feature is a single target, say //components/foo, and the targets
+#   depending on foo need to have some define set if foo is enabled: (1) Write
+#   a declare_args block in foo's BUILD.gn file listing your enable_foo build
+#   flag. (2) Write a config in that file listing the define, and list that
+#   config in foo's public_configs. This will propagate that define to all the
+#   targets depending on foo. (3) When foo is not enabled, just make it expand
+#   to an empty group (or whatever's appropriate for the "off" state of your
+#   feature.
+#
+# - If a semi-random set of targets need to know about a define: (1) In the
+#   lowest level of the build that knows about this feature, add a declare_args
+#   block in the build file for your enable flag. (2) Write a config that adds
+#   a define conditionally based on that build flags. (3) Manually add that
+#   config to the "configs" applying to the targets that need the define.
+#
+# - If a semi-random set of targets need to know about the build flag (to do
+#   file inclusion or exclusion, more than just defines): (1) Write a .gni file
+#   in the lowest-level directory that knows about the feature. (2) Put the
+#   declare_args block with your build flag in that .gni file. (3) Import that
+#   .gni file from the BUILD.gn files that need the flag.
+#
+# Other advice:
+#
+# - Use boolean values when possible. If you need a default value that expands
+#   to some complex thing in the default case (like the location of the
+#   compiler which would be computed by a script), use a default value of -1 or
+#   the empty string. Outside of the declare_args block, conditionally expand
+#   the default value as necessary.
+#
+# - Use a name like "use_foo" or "is_foo" (whatever is more appropriate for
+#   your feature) rather than just "foo".
+#
+# - Write good comments directly above the declaration with no blank line.
+#   These comments will appear as documentation in "gn args --list".
+#
+# - Don't call exec_script inside declare_args. This will execute the script
+#   even if the value is overridden, which is wasteful. See first bullet.
+
+declare_args() {
+  # How many symbols to include in the build. This affects the performance of
+  # the build since the symbols are large and dealing with them is slow.
+  #   2 means regular build with symbols.
+  #   1 means minimal symbols, usually enough for backtraces only.
+  #   0 means no symbols.
+  #   -1 means auto-set (off in release, regular in debug).
+  symbol_level = -1
+
+  # Component build.
+  is_component_build = false
+
+  # Debug build.
+  is_debug = true
+
+  # Whether we're a traditional desktop unix.
+  is_desktop_linux = current_os == "linux" && current_os != "chromeos"
+
+  # Set to true when compiling with the Clang compiler. Typically this is used
+  # to configure warnings.
+  is_clang = current_os == "mac" || current_os == "ios" ||
+             current_os == "linux" || current_os == "chromeos"
+
+  # Compile for Address Sanitizer to find memory bugs.
+  is_asan = false
+
+  # Compile for Leak Sanitizer to find leaks.
+  is_lsan = false
+
+  # Compile for Memory Sanitizer to find uninitialized reads.
+  is_msan = false
+
+  # Compile for Thread Sanitizer to find threading bugs.
+  is_tsan = false
+
+  if (current_os == "chromeos") {
+    # Allows the target toolchain to be injected as arguments. This is needed
+    # to support the CrOS build system which supports per-build-configuration
+    # toolchains.
+    cros_use_custom_toolchain = false
+  }
+
+  # DON'T ADD MORE FLAGS HERE. Read the comment above.
+}
+
+# =============================================================================
+# OS DEFINITIONS
+# =============================================================================
+#
+# We set these various is_FOO booleans for convenience in writing OS-based
+# conditions.
+#
+# - is_android, is_chromeos, is_ios, and is_win should be obvious.
+# - is_mac is set only for desktop Mac. It is not set on iOS.
+# - is_posix is true for mac and any Unix-like system (basically everything
+#   except Windows).
+# - is_linux is true for desktop Linux and ChromeOS, but not Android (which is
+#   generally too different despite being based on the Linux kernel).
+#
+# Do not add more is_* variants here for random lesser-used Unix systems like
+# aix or one of the BSDs. If you need to check these, just check the
+# current_os value directly.
+
+if (current_os == "win") {
+  is_android = false
+  is_chromeos = false
+  is_fnl = false
+  is_ios = false
+  is_linux = false
+  is_mac = false
+  is_nacl = false
+  is_posix = false
+  is_win = true
+} else if (current_os == "mac") {
+  is_android = false
+  is_chromeos = false
+  is_fnl = false
+  is_ios = false
+  is_linux = false
+  is_mac = true
+  is_nacl = false
+  is_posix = true
+  is_win = false
+} else if (current_os == "android") {
+  is_android = true
+  is_chromeos = false
+  is_fnl = false
+  is_ios = false
+  is_linux = false
+  is_mac = false
+  is_nacl = false
+  is_posix = true
+  is_win = false
+} else if (current_os == "chromeos") {
+  is_android = false
+  is_chromeos = true
+  is_fnl = false
+  is_ios = false
+  is_linux = true
+  is_mac = false
+  is_nacl = false
+  is_posix = true
+  is_win = false
+} else if (current_os == "nacl") {
+  # current_os == "nacl" will be passed by the nacl toolchain definition.
+  # It is not set by default or on the command line. We treat is as a
+  # Posix variant.
+  is_android = false
+  is_chromeos = false
+  is_fnl = false
+  is_ios = false
+  is_linux = false
+  is_mac = false
+  is_nacl = true
+  is_posix = true
+  is_win = false
+} else if (current_os == "ios") {
+  is_android = false
+  is_chromeos = false
+  is_fnl = false
+  is_ios = true
+  is_linux = false
+  is_mac = false
+  is_nacl = false
+  is_posix = true
+  is_win = false
+} else if (current_os == "linux") {
+  is_android = false
+  is_chromeos = false
+  is_fnl = false
+  is_ios = false
+  is_linux = true
+  is_mac = false
+  is_nacl = false
+  is_posix = true
+  is_win = false
+} else if (current_os == "fnl") {
+  is_android = false
+  is_chromeos = false
+  is_fnl = true
+  is_ios = false
+  is_linux = true
+  is_mac = false
+  is_nacl = false
+  is_posix = true
+  is_win = false
+}
+
+# =============================================================================
+# SOURCES FILTERS
+# =============================================================================
+#
+# These patterns filter out platform-specific files when assigning to the
+# sources variable. The magic variable |sources_assignment_filter| is applied
+# to each assignment or appending to the sources variable and matches are
+# automatcally removed.
+#
+# Note that the patterns are NOT regular expressions. Only "*" and "\b" (path
+# boundary = end of string or slash) are supported, and the entire string
+# muct match the pattern (so you need "*.cc" to match all .cc files, for
+# example).
+
+# DO NOT ADD MORE PATTERNS TO THIS LIST, see set_sources_assignment_filter call
+# below.
+sources_assignment_filter = []
+if (!is_posix) {
+  sources_assignment_filter += [
+    "*_posix.h",
+    "*_posix.cc",
+    "*_posix_unittest.h",
+    "*_posix_unittest.cc",
+    "*\bposix/*",
+  ]
+}
+if (!is_win) {
+  sources_assignment_filter += [
+    "*_win.cc",
+    "*_win.h",
+    "*_win_unittest.cc",
+    "*\bwin/*",
+    "*.def",
+    "*.rc",
+  ]
+}
+if (!is_mac) {
+  sources_assignment_filter += [
+    "*_mac.h",
+    "*_mac.cc",
+    "*_mac.mm",
+    "*_mac_unittest.h",
+    "*_mac_unittest.cc",
+    "*_mac_unittest.mm",
+    "*\bmac/*",
+    "*_cocoa.h",
+    "*_cocoa.cc",
+    "*_cocoa.mm",
+    "*_cocoa_unittest.h",
+    "*_cocoa_unittest.cc",
+    "*_cocoa_unittest.mm",
+    "*\bcocoa/*",
+  ]
+}
+if (!is_ios) {
+  sources_assignment_filter += [
+    "*_ios.h",
+    "*_ios.cc",
+    "*_ios.mm",
+    "*_ios_unittest.h",
+    "*_ios_unittest.cc",
+    "*_ios_unittest.mm",
+    "*\bios/*",
+  ]
+}
+if (!is_mac && !is_ios) {
+  sources_assignment_filter += [ "*.mm" ]
+}
+if (!is_linux) {
+  sources_assignment_filter += [
+    "*_linux.h",
+    "*_linux.cc",
+    "*_linux_unittest.h",
+    "*_linux_unittest.cc",
+    "*\blinux/*",
+  ]
+}
+if (!is_android) {
+  sources_assignment_filter += [
+    "*_android.h",
+    "*_android.cc",
+    "*_android_unittest.h",
+    "*_android_unittest.cc",
+    "*\bandroid/*",
+  ]
+}
+if (!is_chromeos) {
+  sources_assignment_filter += [
+    "*_chromeos.h",
+    "*_chromeos.cc",
+    "*_chromeos_unittest.h",
+    "*_chromeos_unittest.cc",
+    "*\bchromeos/*",
+  ]
+}
+
+# DO NOT ADD MORE PATTERNS TO THIS LIST, see set_sources_assignment_filter call
+# below.
+
+# Actually save this list.
+#
+# These patterns are executed for every file in the source tree of every run.
+# Therefore, adding more patterns slows down the build for everybody. We should
+# only add automatic patterns for configurations affecting hundreds of files
+# across many projects in the tree.
+#
+# Therefore, we only add rules to this list corresponding to platforms on the
+# Chromium waterfall.  This is not for non-officially-supported platforms
+# (FreeBSD, etc.) toolkits, (X11, GTK, etc.), or features. For these cases,
+# write a conditional in the target to remove the file(s) from the list when
+# your platform/toolkit/feature doesn't apply.
+set_sources_assignment_filter(sources_assignment_filter)
+
+# =============================================================================
+# BUILD OPTIONS
+# =============================================================================
+
+# These Sanitizers all imply using the Clang compiler. On Windows they either
+# don't work or work differently.
+if (!is_clang && (is_asan || is_lsan || is_tsan || is_msan)) {
+  is_clang = true
+}
+
+# =============================================================================
+# TARGET DEFAULTS
+# =============================================================================
+#
+# Set up the default configuration for every build target of the given type.
+# The values configured here will be automatically set on the scope of the
+# corresponding target. Target definitions can add or remove to the settings
+# here as needed.
+
+# Holds all configs used for making native executables and libraries, to avoid
+# duplication in each target below.
+_native_compiler_configs = [
+  "//build/config:feature_flags",
+  "//build/config/compiler:compiler",
+  "//build/config/compiler:compiler_arm_fpu",
+  "//build/config/compiler:chromium_code",
+  "//build/config/compiler:default_include_dirs",
+  "//build/config/compiler:no_rtti",
+  "//build/config/compiler:runtime_library",
+]
+if (is_win) {
+  _native_compiler_configs += [
+    "//build/config/win:lean_and_mean",
+    "//build/config/win:nominmax",
+    "//build/config/win:sdk",
+    "//build/config/win:unicode",
+    "//build/config/win:winver",
+  ]
+}
+if (is_posix) {
+  _native_compiler_configs += [
+    "//build/config/gcc:no_exceptions",
+    "//build/config/gcc:symbol_visibility_hidden",
+  ]
+}
+
+if (is_fnl) {
+  _native_compiler_configs += [ "//build/config/fnl:sdk" ]
+} else if (is_linux) {
+  _native_compiler_configs += [ "//build/config/linux:sdk" ]
+} else if (is_mac) {
+  _native_compiler_configs += [ "//build/config/mac:sdk" ]
+} else if (is_ios) {
+  _native_compiler_configs += [ "//build/config/ios:sdk" ]
+} else if (is_android) {
+  _native_compiler_configs += [ "//build/config/android:sdk" ]
+}
+
+if (is_clang) {
+  _native_compiler_configs += [
+    "//build/config/clang:find_bad_constructs",
+    "//build/config/clang:extra_warnings",
+  ]
+}
+
+# Optimizations and debug checking.
+if (is_debug) {
+  _native_compiler_configs += [ "//build/config:debug" ]
+  _default_optimization_config = "//build/config/compiler:no_optimize"
+} else {
+  _native_compiler_configs += [ "//build/config:release" ]
+  _default_optimization_config = "//build/config/compiler:optimize"
+}
+_native_compiler_configs += [ _default_optimization_config ]
+
+# If it wasn't manually set, set to an appropriate default.
+if (symbol_level == -1) {
+  # Linux is slowed by having symbols as part of the target binary, whereas
+  # Mac and Windows have them separate, so in Release Linux, default them off.
+  if (is_debug || !is_linux) {
+    symbol_level = 2
+  } else if (is_asan || is_lsan || is_tsan || is_msan) {
+    # Sanitizers require symbols for filename suppressions to work.
+    symbol_level = 1
+  } else {
+    symbol_level = 0
+  }
+}
+
+# Symbol setup.
+if (symbol_level == 2) {
+  _default_symbols_config = "//build/config/compiler:symbols"
+} else if (symbol_level == 1) {
+  _default_symbols_config = "//build/config/compiler:minimal_symbols"
+} else if (symbol_level == 0) {
+  _default_symbols_config = "//build/config/compiler:no_symbols"
+} else {
+  assert(false, "Bad value for symbol_level.")
+}
+_native_compiler_configs += [ _default_symbols_config ]
+
+# Windows linker setup for EXEs and DLLs.
+if (is_win) {
+  _windows_linker_configs = [
+    "//build/config/win:default_incremental_linking",
+    "//build/config/win:sdk_link",
+    "//build/config/win:common_linker_setup",
+
+    # Default to console-mode apps. Most of our targets are tests and such
+    # that shouldn't use the windows subsystem.
+    "//build/config/win:console",
+  ]
+}
+
+# Executable defaults.
+_executable_configs =
+    _native_compiler_configs + [ "//build/config:default_libs" ]
+if (is_win) {
+  _executable_configs += _windows_linker_configs
+} else if (is_mac) {
+  _executable_configs += [
+    "//build/config/mac:mac_dynamic_flags",
+    "//build/config/mac:mac_executable_flags",
+  ]
+} else if (is_linux || is_android) {
+  _executable_configs += [ "//build/config/gcc:executable_ldconfig" ]
+  if (is_android) {
+    _executable_configs += [ "//build/config/android:executable_config" ]
+  }
+}
+set_defaults("executable") {
+  configs = _executable_configs
+}
+
+# Static library defaults.
+set_defaults("static_library") {
+  configs = _native_compiler_configs
+}
+
+# Shared library defaults (also for components in component mode).
+_shared_library_configs =
+    _native_compiler_configs + [ "//build/config:default_libs" ]
+if (is_win) {
+  _shared_library_configs += _windows_linker_configs
+} else if (is_mac) {
+  _shared_library_configs += [ "//build/config/mac:mac_dynamic_flags" ]
+} else if (is_android) {
+  # Strip native JNI exports from shared libraries by default. Binaries that
+  # want this can remove this config.
+  _shared_library_configs +=
+      [ "//build/config/android:hide_native_jni_exports" ]
+}
+set_defaults("shared_library") {
+  configs = _shared_library_configs
+}
+if (is_component_build) {
+  set_defaults("component") {
+    configs = _shared_library_configs
+  }
+}
+
+# Source set defaults (also for components in non-component mode).
+set_defaults("source_set") {
+  configs = _native_compiler_configs
+}
+if (!is_component_build) {
+  set_defaults("component") {
+    configs = _native_compiler_configs
+  }
+}
+
+# Test defaults.
+set_defaults("test") {
+  if (is_android) {
+    configs = _shared_library_configs
+  } else {
+    configs = _executable_configs
+  }
+}
+
+# ==============================================================================
+# TOOLCHAIN SETUP
+# ==============================================================================
+#
+# Here we set the default toolchain, as well as the variable host_toolchain
+# which will identify the toolchain corresponding to the local system when
+# doing cross-compiles. When not cross-compiling, this will be the same as the
+# default toolchain.
+
+if (is_win) {
+  # On windows we use the same toolchain for host and target by default.
+  if (is_clang) {
+    host_toolchain = "//build/toolchain/win:clang_$current_cpu"
+  } else {
+    host_toolchain = "//build/toolchain/win:$current_cpu"
+  }
+  set_default_toolchain("$host_toolchain")
+} else if (is_android) {
+  if (host_os == "linux") {
+    # Use clang for the x86/64 Linux host builds.
+    if (host_cpu == "x86" || host_cpu == "x64") {
+      host_toolchain = "//build/toolchain/linux:clang_$host_cpu"
+    } else {
+      host_toolchain = "//build/toolchain/linux:$host_cpu"
+    }
+  } else if (host_os == "mac") {
+    host_toolchain = "//build/toolchain/mac:clang_$host_cpu"
+  } else {
+    assert(false, "Unknown host for android cross compile")
+  }
+  if (is_clang) {
+    set_default_toolchain("//build/toolchain/android:clang_$current_cpu")
+  } else {
+    set_default_toolchain("//build/toolchain/android:$current_cpu")
+  }
+} else if (is_linux) {
+  if (is_clang) {
+    host_toolchain = "//build/toolchain/linux:clang_$host_cpu"
+    set_default_toolchain("//build/toolchain/linux:clang_$current_cpu")
+  } else {
+    host_toolchain = "//build/toolchain/linux:$host_cpu"
+    set_default_toolchain("//build/toolchain/linux:$current_cpu")
+  }
+  if (is_chromeos && cros_use_custom_toolchain) {
+    set_default_toolchain("//build/toolchain/cros:target")
+  }
+  if (is_fnl) {
+    set_default_toolchain("//build/toolchain/fnl:target")
+  }
+} else if (is_mac) {
+  host_toolchain = "//build/toolchain/mac:clang_x64"
+  set_default_toolchain(host_toolchain)
+} else if (is_ios) {
+  host_toolchain = "//build/toolchain/mac:clang_x64"
+  if (use_ios_simulator) {
+    set_default_toolchain("//build/toolchain/mac:ios_clang_x64")
+  } else {
+    set_default_toolchain("//build/toolchain/mac:ios_clang_arm")
+  }
+} else if (is_nacl) {
+  # TODO(GYP): This will need to change when we get NaCl working
+  # on multiple platforms, but this whole block of code (how we define
+  # host_toolchain) needs to be reworked regardless to key off of host_os
+  # and host_cpu rather than the is_* variables.
+  host_toolchain = "//build/toolchain/linux:clang_x64"
+}
+
+# ==============================================================================
+# COMPONENT SETUP
+# ==============================================================================
+
+# TODO(brettw) erase this once the built-in "component" function is removed.
+if (is_component_build) {
+  component_mode = "shared_library"
+} else {
+  component_mode = "source_set"
+}
+
+template("component") {
+  if (is_component_build) {
+    shared_library(target_name) {
+      # Configs will always be defined since we set_defaults for a component
+      # above. We want to use those rather than whatever came with the nested
+      # shared/static library inside the component.
+      configs = []  # Prevent list overwriting warning.
+      configs = invoker.configs
+
+      # The sources assignment filter will have already been applied when the
+      # code was originally executed. We don't want to apply it again, since
+      # the original target may have override it for some assignments.
+      set_sources_assignment_filter([])
+
+      if (defined(invoker.all_dependent_configs)) {
+        all_dependent_configs = invoker.all_dependent_configs
+      }
+      if (defined(invoker.allow_circular_includes_from)) {
+        allow_circular_includes_from = invoker.allow_circular_includes_from
+      }
+      if (defined(invoker.cflags)) {
+        cflags = invoker.cflags
+      }
+      if (defined(invoker.cflags_c)) {
+        cflags_c = invoker.cflags_c
+      }
+      if (defined(invoker.cflags_cc)) {
+        cflags_cc = invoker.cflags_cc
+      }
+      if (defined(invoker.cflags_objc)) {
+        cflags_objc = invoker.cflags_objc
+      }
+      if (defined(invoker.cflags_objcc)) {
+        cflags_objcc = invoker.cflags_objcc
+      }
+      if (defined(invoker.check_includes)) {
+        check_includes = invoker.check_includes
+      }
+      if (defined(invoker.data)) {
+        data = invoker.data
+      }
+      if (defined(invoker.data_deps)) {
+        data_deps = invoker.data_deps
+      }
+      if (defined(invoker.datadeps)) {
+        datadeps = invoker.datadeps
+      }
+      if (defined(invoker.defines)) {
+        defines = invoker.defines
+      }
+
+      # All shared libraries must have the sanitizer deps to properly link in
+      # asan mode (this target will be empty in other cases).
+      if (defined(invoker.deps)) {
+        deps = invoker.deps + [ "//build/config/sanitizers:deps" ]
+      } else {
+        deps = [
+          "//build/config/sanitizers:deps",
+        ]
+      }
+      if (defined(invoker.direct_dependent_configs)) {
+        direct_dependent_configs = invoker.direct_dependent_configs
+      }
+      if (defined(invoker.forward_dependent_configs_from)) {
+        forward_dependent_configs_from = invoker.forward_dependent_configs_from
+      }
+      if (defined(invoker.include_dirs)) {
+        include_dirs = invoker.include_dirs
+      }
+      if (defined(invoker.ldflags)) {
+        ldflags = invoker.ldflags
+      }
+      if (defined(invoker.lib_dirs)) {
+        lib_dirs = invoker.lib_dirs
+      }
+      if (defined(invoker.libs)) {
+        libs = invoker.libs
+      }
+      if (defined(invoker.output_extension)) {
+        output_extension = invoker.output_extension
+      }
+      if (defined(invoker.output_name)) {
+        output_name = invoker.output_name
+      }
+      if (defined(invoker.public)) {
+        public = invoker.public
+      }
+      if (defined(invoker.public_configs)) {
+        public_configs = invoker.public_configs
+      }
+      if (defined(invoker.public_deps)) {
+        public_deps = invoker.public_deps
+      }
+      if (defined(invoker.sources)) {
+        sources = invoker.sources
+      }
+      if (defined(invoker.testonly)) {
+        testonly = invoker.testonly
+      }
+      if (defined(invoker.visibility)) {
+        visibility = invoker.visibility
+      }
+    }
+  } else {
+    source_set(target_name) {
+      # See above.
+      configs = []  # Prevent list overwriting warning.
+      configs = invoker.configs
+
+      # See above call.
+      set_sources_assignment_filter([])
+
+      if (defined(invoker.all_dependent_configs)) {
+        all_dependent_configs = invoker.all_dependent_configs
+      }
+      if (defined(invoker.allow_circular_includes_from)) {
+        allow_circular_includes_from = invoker.allow_circular_includes_from
+      }
+      if (defined(invoker.cflags)) {
+        cflags = invoker.cflags
+      }
+      if (defined(invoker.cflags_c)) {
+        cflags_c = invoker.cflags_c
+      }
+      if (defined(invoker.cflags_cc)) {
+        cflags_cc = invoker.cflags_cc
+      }
+      if (defined(invoker.cflags_objc)) {
+        cflags_objc = invoker.cflags_objc
+      }
+      if (defined(invoker.cflags_objcc)) {
+        cflags_objcc = invoker.cflags_objcc
+      }
+      if (defined(invoker.check_includes)) {
+        check_includes = invoker.check_includes
+      }
+      if (defined(invoker.data)) {
+        data = invoker.data
+      }
+      if (defined(invoker.data_deps)) {
+        data_deps = invoker.data_deps
+      }
+      if (defined(invoker.datadeps)) {
+        datadeps = invoker.datadeps
+      }
+      if (defined(invoker.defines)) {
+        defines = invoker.defines
+      }
+      if (defined(invoker.deps)) {
+        deps = invoker.deps
+      }
+      if (defined(invoker.direct_dependent_configs)) {
+        direct_dependent_configs = invoker.direct_dependent_configs
+      }
+      if (defined(invoker.forward_dependent_configs_from)) {
+        forward_dependent_configs_from = invoker.forward_dependent_configs_from
+      }
+      if (defined(invoker.include_dirs)) {
+        include_dirs = invoker.include_dirs
+      }
+      if (defined(invoker.ldflags)) {
+        ldflags = invoker.ldflags
+      }
+      if (defined(invoker.lib_dirs)) {
+        lib_dirs = invoker.lib_dirs
+      }
+      if (defined(invoker.libs)) {
+        libs = invoker.libs
+      }
+      if (defined(invoker.output_extension)) {
+        output_extension = invoker.output_extension
+      }
+      if (defined(invoker.output_name)) {
+        output_name = invoker.output_name
+      }
+      if (defined(invoker.public)) {
+        public = invoker.public
+      }
+      if (defined(invoker.public_configs)) {
+        public_configs = invoker.public_configs
+      }
+      if (defined(invoker.public_deps)) {
+        public_deps = invoker.public_deps
+      }
+      if (defined(invoker.sources)) {
+        sources = invoker.sources
+      }
+      if (defined(invoker.testonly)) {
+        testonly = invoker.testonly
+      }
+      if (defined(invoker.visibility)) {
+        visibility = invoker.visibility
+      }
+    }
+  }
+}