toolchain_build: Force GCC build to recognize "system" limits.h

toolchain_build/toolchain_build.py

 #!/usr/bin/python
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Recipes for NativeClient toolchain packages.
 
 The real entry plumbing is in toolchain_main.py.
 """
 
@@ skipping 288 matching lines @@
                   'libitm',
                   'libjava',
                   'libmudflap',
                   'libobjc',
                   'libquadmath',
                   'libssp',
                   'libstdc++-v3',
                   ]],
           'commands': ConfigureTargetPrep(target) + [
               ConfigureGccCommand(target),
-              GccCommand(target, MAKE_PARALLEL_CMD + ['all-gcc']),
+              # gcc/Makefile's install rules ordinarily look at the
+              # installed include directory for a limits.h to decide
+              # whether the lib/gcc/.../include-fixed/limits.h header
+              # should be made to expect a libc-supplied limits.h or not.
+              # Since we're doing this build in a clean environment without
+              # any libc installed, we need to force its hand here.
+              GccCommand(target, MAKE_PARALLEL_CMD + ['all-gcc',
+                                                      'LIMITS_H_TEST=true']),
               # gcc/Makefile's install targets populate this directory
               # only if it already exists.
               command.Mkdir(os.path.join('%(output)s', target + '-nacl', 'bin'),
                             True),
               GccCommand(target, MAKE_DESTDIR_CMD + ['install-strip-gcc']),
               REMOVE_INFO_DIR,
               ],
           },
       }
   return tools
@@ skipping 135 matching lines @@
 
 
 PACKAGES = CollectPackages(TARGET_LIST)
 
 
 if __name__ == '__main__':
   tb = toolchain_main.PackageBuilder(PACKAGES, sys.argv[1:])
   # TODO(mcgrathr): The bot ought to run some native_client tests
   # using the new toolchain, like the old x86 toolchain bots do.
   tb.Main()