Fix broken pipe caused by commands in toolchain.gypi.

build/toolchain.gypi

 # Copyright 2013 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 358 matching lines @@
       }],
       ['(OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris" \
          or OS=="netbsd" or OS=="mac" or OS=="android") and \
         (v8_target_arch=="arm" or v8_target_arch=="ia32" or \
          v8_target_arch=="mipsel")', {
         # Check whether the host compiler and target compiler support the
         # '-m32' option and set it if so.
         'target_conditions': [
           ['_toolset=="host"', {
             'variables': {
-              'm32flag': '<!((echo | $(echo ${CXX_host:-$(which g++)}) -m32 -E - > /dev/null 2>&1) && echo "-m32" || true)',
+              'm32flag': '<!(($(echo ${CXX_host:-$(which g++)}) -m32 -E - > /dev/null 2>&1 < /dev/null) && echo "-m32" || true)',
             },
             'cflags': [ '<(m32flag)' ],
             'ldflags': [ '<(m32flag)' ],
             'xcode_settings': {
               'ARCHS': [ 'i386' ],
             },
           }],
           ['_toolset=="target"', {
             'variables': {
-              'm32flag': '<!((echo | $(echo ${CXX_target:-<(CXX)}) -m32 -E - > /dev/null 2>&1) && echo "-m32" || true)',
+              'm32flag': '<!(($(echo ${CXX_target:-<(CXX)}) -m32 -E - > /dev/null 2>&1 < /dev/null) && echo "-m32" || true)',
               'clang%': 0,
             },
             'conditions': [
               ['(OS!="android" or clang==1) and \
                 nacl_target_arch!="nacl_x64"', {
                 'cflags': [ '<(m32flag)' ],
                 'ldflags': [ '<(m32flag)' ],
               }],
             ],
             'xcode_settings': {
               'ARCHS': [ 'i386' ],
             },
           }],
         ],
       }],
       ['(OS=="linux") and (v8_target_arch=="x64")', {
         # Check whether the host compiler and target compiler support the
         # '-m64' option and set it if so.
         'target_conditions': [
           ['_toolset=="host"', {
             'variables': {
-              'm64flag': '<!((echo | $(echo ${CXX_host:-$(which g++)}) -m64 -E - > /dev/null 2>&1) && echo "-m64" || true)',
+              'm64flag': '<!(($(echo ${CXX_host:-$(which g++)}) -m64 -E - > /dev/null 2>&1 < /dev/null) && echo "-m64" || true)',
             },
             'cflags': [ '<(m64flag)' ],
             'ldflags': [ '<(m64flag)' ],
           }],
           ['_toolset=="target"', {
             'variables': {
-              'm64flag': '<!((echo | $(echo ${CXX_target:-<(CXX)}) -m64 -E - > /dev/null 2>&1) && echo "-m64" || true)',
+              'm64flag': '<!(($(echo ${CXX_target:-<(CXX)}) -m64 -E - > /dev/null 2>&1 < /dev/null) && echo "-m64" || true)',
             },
             'cflags': [ '<(m64flag)' ],
             'ldflags': [ '<(m64flag)' ],
           }]
         ],
       }],
       ['OS=="freebsd" or OS=="openbsd"', {
         'cflags': [ '-I/usr/local/include' ],
       }],
       ['OS=="netbsd"', {
@@ skipping 253 matching lines @@
                 'OptimizeReferences': '2',
                 'EnableCOMDATFolding': '2',
               },
             },
           }],  # OS=="win"
         ],  # conditions
       },  # Release
     },  # configurations
   },  # target_defaults
 }