Disable sysroot option when clang build is disabled

build/common.gypi

 # Copyright (c) 2012 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 18 matching lines @@
 
             # Whether or not we are building the Ash shell.
             'use_ash%': 0,
 
             # Whether or not we are using CRAS, the ChromeOS Audio Server.
             'use_cras%': 0,
 
             # Use a raw surface abstraction.
             'use_ozone%': 0,
 
+            # By default we build against a stable sysroot image to avoid
+            # depending on the packages installed on the local machine. Set this
+            # to 0 to build against locally installed headers and libraries (e.g.
+            # if packaging for a linux distro)
+            'use_sysroot%': 1,
+
             # Configure the build for small devices. See crbug.com/318413
             'embedded%': 0,
 
             'conditions': [
               # Compute the architecture that we're building on.
               ['OS=="win" or OS=="ios"', {
                 'host_arch%': 'ia32',
               }, {
                 'host_arch%': '<!pymod_do_main(detect_host_arch)',
               }],
             ],
           },
           # Copy conditionally-set variables out one scope.
           'chromeos%': '<(chromeos)',
           'chromecast%': '<(chromecast)',
           'use_aura%': '<(use_aura)',
           'use_ash%': '<(use_ash)',
           'use_cras%': '<(use_cras)',
           'use_ozone%': '<(use_ozone)',
           'embedded%': '<(embedded)',
           'host_arch%': '<(host_arch)',
+          'use_sysroot%': '<(use_sysroot)',
 
           # Whether we are using Views Toolkit
           'toolkit_views%': 0,
 
           # Use the PCI lib to collect GPU information.
           'use_libpci%': 1,
 
           # Use OpenSSL instead of NSS as the underlying SSL and crypto
           # implementation. Certificate verification will in most cases be
           # handled by the OS. If OpenSSL's struct X509 is used to represent
@@ skipping 11 matching lines @@
 
           # Enable HiDPI support.
           'enable_hidpi%': 0,
 
           # Enable top chrome material design.
           'enable_topchrome_md%' : 0,
 
           # Enable Wayland display server support.
           'enable_wayland_server%' : 0,
 
-          # By default we build against a stable sysroot image to avoid
-          # depending on the packages installed on the local machine. Set this
-          # to 0 to build against locally installed headers and libraries (e.g.
-          # if packaging for a linux distro)
-          'use_sysroot%': 1,
+          # Set this to true when building with Clang.
+          # See http://code.google.com/p/chromium/wiki/Clang for details.
+          # If this is set, clang is used as both host and target compiler in
+          # cross-compile builds.
+          'clang%': 0,
 
           # Override buildtype to select the desired build flavor.
           # Dev - everyday build for development/testing
           # Official - release build (generally implies additional processing)
           # TODO(mmoss) Once 'buildtype' is fully supported (e.g. Windows gyp
           # conversion is done), some of the things which are now controlled by
           # 'branding', such as symbol generation, will need to be refactored
           # based on 'buildtype' (i.e. we don't care about saving symbols for
           # non-Official # builds).
           'buildtype%': 'Dev',
 
           # Override branding to select the desired branding flavor.
           'branding%': 'Chromium',
 
           'conditions': [
             # Windows and Linux (including Chrome OS) use Aura and Ash.
             ['OS=="win" or OS=="linux"', {
               'use_ash%': 1,
               'use_aura%': 1,
             }],
 
+            # Turn off use_sysroot when clang build is disabled.
+            # System headers for gcc > 4.6 aren't available at sysroot location.
+            # If clang build is disabled and gcc > 4.6, ToT builds fail.
+            # https://code.google.com/p/chromium/issues/detail?id=504446#c17
+            # TODO(kphanee): Can we check for gcc_version here somehow?
+            ['use_sysroot==1 and clang==0', {
+              'use_sysroot%': 0,
+            }],
+
             ['chromecast==1', {
               'use_libpci': 0,
               'conditions': [
                 ['OS!="android"', {
                   'embedded%': 1,
                   'use_ozone%': 1,
                 }],
               ],
             }],
 
@@ skipping 37 matching lines @@
         'use_openssl_certs%': '<(use_openssl_certs)',
         'enable_viewport%': '<(enable_viewport)',
         'enable_hidpi%': '<(enable_hidpi)',
         'enable_topchrome_md%': '<(enable_topchrome_md)',
         'enable_wayland_server%': '<(enable_wayland_server)',
         'buildtype%': '<(buildtype)',
         'branding%': '<(branding)',
         'branding_path_component%': '<(branding)',
         'host_arch%': '<(host_arch)',
         'target_arch%': '<(target_arch)',
+        'clang%': '<(clang)',
 
         'target_subarch%': '',
 
         # The channel to build on Android: stable, beta, dev, canary, or
         # default. "default" should be used on non-official builds.
         'android_channel%': 'default',
 
         # Set ARM architecture version.
         'arm_version%': 7,
 
@@ skipping 164 matching lines @@
       'enable_wayland_server%': '<(enable_wayland_server)',
       'android_channel%': '<(android_channel)',
       'use_goma%': '<(use_goma)',
       'gomadir%': '<(gomadir)',
       'enable_app_list%': '<(enable_app_list)',
       'use_default_render_theme%': '<(use_default_render_theme)',
       'buildtype%': '<(buildtype)',
       'branding%': '<(branding)',
       'branding_path_component%': '<(branding_path_component)',
       'arm_version%': '<(arm_version)',
+      'clang%': '<(clang)',
       'sysroot%': '<(sysroot)',
       'chroot_cmd%': '<(chroot_cmd)',
       'system_libdir%': '<(system_libdir)',
 
       # Set to 1 to enable fast builds. Set to 2 for even faster builds
       # (it disables debug info for fastest compilation - only for use
       # on compile-only bots).
       'fastbuild%': 0,
 
       # Set to 1 to not store any build metadata, e.g. ifdef out all __DATE__
@@ skipping 250 matching lines @@
       # (disabled) in ~/.gyp/include.gypi or via the GYP command line.
       # This setting will override the default.
       #
       # See
       # http://code.google.com/p/chromium/wiki/WindowsPrecompiledHeaders
       # for details.
       'chromium_win_pch%': 0,
 
       # Clang stuff.
       'make_clang_dir%': 'third_party/llvm-build/Release+Asserts',
-      # Set this to true when building with Clang.
-      # See http://code.google.com/p/chromium/wiki/Clang for details.
-      # If this is set, clang is used as both host and target compiler in
-      # cross-compile builds.
-      'clang%': 0,
 
       # Use experimental lld linker instead of the platform's default linker.
       'use_lld%': 0,
 
       # Enable plugin installation by default.
       'enable_plugin_installation%': 1,
 
       # Specifies whether to use canvas_skia.cc in place of platform
       # specific implementations of gfx::Canvas. Affects text drawing in the
       # Chrome UI.
@@ skipping 5728 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }