Support private values in GN.

build/config/BUILDCONFIG.gn

 # 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.
 
 # =============================================================================
 # BUILD FLAGS
 # =============================================================================
 #
 # This block lists input arguments to the build, along with their default
 # values. GN requires listing them explicitly so it can validate input and have
@@ skipping 162 matching lines @@
 
 # =============================================================================
 # 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.
 #
-# We define lists of filters for each platform for all builds so they can
-# be used by individual targets if necessary (a target can always change
-# sources_assignment_filter on itself if it needs something more specific).
-#
 # 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.
-windows_sources_filters = [
-  "*_win.cc",
-  "*_win.h",
-  "*_win_unittest.cc",
-  "*\bwin/*",
-  "*.rc",
-]
-mac_sources_filters = [
-  "*_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/*",
-]
-ios_sources_filters = [
-  "*_ios.h",
-  "*_ios.cc",
-  "*_ios.mm",
-  "*_ios_unittest.h",
-  "*_ios_unittest.cc",
-  "*_ios_unittest.mm",
-  "*\bios/*",
-]
-objective_c_sources_filters = [
-  "*.mm",
-]
-linux_sources_filters = [
-  "*_linux.h",
-  "*_linux.cc",
-  "*_linux_unittest.h",
-  "*_linux_unittest.cc",
-  "*\blinux/*",
-]
-android_sources_filters = [
-  "*_android.h",
-  "*_android.cc",
-  "*_android_unittest.h",
-  "*_android_unittest.cc",
-  "*\bandroid/*",
-]
-posix_sources_filters = [
-  "*_posix.h",
-  "*_posix.cc",
-  "*_posix_unittest.h",
-  "*_posix_unittest.cc",
-  "*\bposix/*",
-]
-chromeos_sources_filters = [
-  "*_chromeos.h",
-  "*_chromeos.cc",
-  "*_chromeos_unittest.h",
-  "*_chromeos_unittest.cc",
-  "*\bchromeos/*",
-]
+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/*",
+    "*.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.
 
-# Construct the full list of sources we're using for this platform.
-sources_assignment_filter = []
-if (is_win) {
-  sources_assignment_filter += posix_sources_filters
-} else {
-  sources_assignment_filter += windows_sources_filters
-}
-if (!is_mac) {
-  sources_assignment_filter += mac_sources_filters
-}
-if (!is_ios) {
-  sources_assignment_filter += ios_sources_filters
-}
-if (!is_mac && !is_ios) {
-  sources_assignment_filter += objective_c_sources_filters
-}
-if (!is_linux) {
-  sources_assignment_filter += linux_sources_filters
-}
-if (!is_android) {
-  sources_assignment_filter += android_sources_filters
-}
-if (!is_chromeos) {
-  sources_assignment_filter += chromeos_sources_filters
-}
-
 # Actually save this list.
 #
-# DO NOT ADD MORE PATTERNS TO 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.
@@ skipping 19 matching lines @@
 # 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 = [
+_native_compiler_configs = [
   "//build/config:feature_flags",
 
   "//build/config/compiler:compiler",
   "//build/config/compiler:chromium_code",
   "//build/config/compiler:default_warnings",
   "//build/config/compiler:no_rtti",
   "//build/config/compiler:runtime_library",
 ]
 if (is_win) {
-  native_compiler_configs += [
+  _native_compiler_configs += [
     "//build/config/win:lean_and_mean",
     "//build/config/win:sdk",
     "//build/config/win:unicode",
   ]
 } else if (is_linux) {
-  native_compiler_configs += [ "//build/config/linux:sdk", ]
+  _native_compiler_configs += [ "//build/config/linux:sdk", ]
 } else if (is_mac) {
-  native_compiler_configs += [ "//build/config/mac:sdk", ]
+  _native_compiler_configs += [ "//build/config/mac:sdk", ]
 } else if (is_ios) {
-  native_compiler_configs += [ "//build/config/ios:sdk", ]
+  _native_compiler_configs += [ "//build/config/ios:sdk", ]
 } else if (is_android) {
-  native_compiler_configs += [ "//build/config/android:sdk", ]
+  _native_compiler_configs += [ "//build/config/android:sdk", ]
 }
 if (!is_win) {
-  native_compiler_configs += [ "//build/config/gcc:symbol_visibility_hidden" ]
+  _native_compiler_configs += [ "//build/config/gcc:symbol_visibility_hidden" ]
 }
 if (is_clang) {
-  native_compiler_configs += [
+  _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"
+  _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 += [ "//build/config:release" ]
+  _default_optimization_config = "//build/config/compiler:optimize"
 }
-native_compiler_configs += [ default_optimization_config ]
+_native_compiler_configs += [ _default_optimization_config ]
 
 # Symbol setup.
 if (is_clang && (is_linux || is_android)) {
   # Clang creates chubby debug information, which makes linking very slow.
   # For now, don't create debug information with clang.
   # See http://crbug.com/70000
   # TODO(brettw) This just copies GYP. Why not do this on Mac as well?
-  default_symbols_config = "//build/config/compiler:no_symbols"
+  _default_symbols_config = "//build/config/compiler:no_symbols"
 } else if (symbol_level == 2) {
-  default_symbols_config = "//build/config/compiler:symbols"
+  _default_symbols_config = "//build/config/compiler:symbols"
 } else if (symbol_level == 1) {
-  default_symbols_config = "//build/config/compiler:minimal_symbols"
+  _default_symbols_config = "//build/config/compiler:minimal_symbols"
 } else if (symbol_level == 0) {
-  default_symbols_config = "//build/config/compiler:no_symbols"
+  _default_symbols_config = "//build/config/compiler:no_symbols"
 } else {
   assert(false, "Bad value for symbol_level.")
 }
-native_compiler_configs += [ default_symbols_config ]
+_native_compiler_configs += [ _default_symbols_config ]
 
 # Windows linker setup for EXEs and DLLs.
 if (is_win) {
   if (is_debug) {
-    default_incremental_linking_config =
+    _default_incremental_linking_config =
       "//build/config/win:incremental_linking"
   } else {
-    default_incremental_linking_config =
+    _default_incremental_linking_config =
       "//build/config/win:no_incremental_linking"
   }
-  windows_linker_configs = [
-    default_incremental_linking_config,
+  _windows_linker_configs = [
+    _default_incremental_linking_config,
     "//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",
   ]
 }
 
 set_defaults("executable") {
-  configs = native_compiler_configs + [
+  configs = _native_compiler_configs + [
     "//build/config:default_libs",
   ]
   if (is_win) {
-    configs += windows_linker_configs
+    configs += _windows_linker_configs
   } else if (is_mac) {
     configs += [
       "//build/config/mac:mac_dynamic_flags",
       "//build/config/mac:mac_executable_flags" ]
   } else if (is_linux || is_android) {
     configs += [ "//build/config/gcc:executable_ldconfig" ]
   }
 }
 
 set_defaults("static_library") {
-  configs = native_compiler_configs
+  configs = _native_compiler_configs
 }
 
 set_defaults("shared_library") {
-  configs = native_compiler_configs + [
+  configs = _native_compiler_configs + [
     "//build/config:default_libs",
   ]
   if (is_win) {
-    configs += windows_linker_configs
+    configs += _windows_linker_configs
   } else if (is_mac) {
     configs += [ "//build/config/mac:mac_dynamic_flags" ]
   }
 }
 
 set_defaults("source_set") {
-  configs = native_compiler_configs
+  configs = _native_compiler_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.
@@ skipping 18 matching lines @@
 } else if (is_linux) {
   host_toolchain = "//build/toolchain/linux:$build_cpu_arch"
   set_default_toolchain("//build/toolchain/linux:$cpu_arch")
 } else if (is_mac) {
   host_toolchain = "//build/toolchain/mac:clang"
   set_default_toolchain(host_toolchain)
 } else if (is_ios) {
   host_toolchain = "//build/toolchain/mac:host_clang"
   set_default_toolchain("//build/toolchain/mac:clang")
 }