Change startup ABI for untrusted code to be C-compatible

src/untrusted/irt/nacl.scons

 # -*- python -*-
 # Copyright (c) 2011 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.
 
 
 Import('env')
 
 # Since the integrated runtime will be built with newlib,
 # there's no need to build this module against glibc.
@@ skipping 20 matching lines @@
 if blob_env.Bit('bitcode'):
   blob_env.Append(LINKFLAGS='-Wl,-Ttext=${IRT_BLOB_CODE_START}')
   # To allow elf_restart_*.o in the link line
   blob_env.Append(LINKFLAGS='--pnacl-allow-native')
   # Without this llc asserts
   # c.f. http://code.google.com/p/nativeclient/issues/detail?id=1225
 #  blob_env.Append(LINKFLAGS=['-O0'])
 else:
   blob_env.Append(LINKFLAGS='-Wl,-Ttext-segment=${IRT_BLOB_CODE_START}')
 
-asm_env = blob_env.Clone()
-if asm_env.Bit('bitcode'):
-  asm_env.Replace(OBJSUFFIX='.o')
-  asm_env.Append(ASFLAGS=['-arch', '${TARGET_FULLARCH}'])
-
-asm_helper = asm_env.ComponentObject(
-    'elf_restart_%s.S' % env['TARGET_FULLARCH'].replace('-', '_'))
-
 irt_support_sources = [
     'irt_entry.c',
     'irt_malloc.c',
     'irt_sbrk.c',
     'irt_elf_utils.c',
     ]
 
 # The bitcode build does not yet use -mtls-use-call and so it improperly
 # pollutes user TLS with IRT-private TLS.  But until that's fixed,
 # overriding the entry points with the irt_tls.c versions would cause a
 # mismatch where library code using (what should be reserved for) user TLS
 # will crash because it hasn't been initialized.
 if not env.Bit('bitcode'):
   irt_support_sources.append('irt_tls.c')
 
 # TODO(mcgrathr): most of these live in ../nacl/irt_*.c now because
 # of the dismal kludge state of building everything.  Eventually
 # all that should move here.
 irt_common_interfaces = []
 
 # These are the objects and libraries that go into every IRT image.
-irt_support_objs = asm_helper + [blob_env.ComponentObject(x) for x in
-                                 (irt_support_sources + irt_common_interfaces)]
+irt_support_objs = [blob_env.ComponentObject(x) for x in
+                    (irt_support_sources + irt_common_interfaces)]
 irt_support_libs = ['pthread']
 
 # These go into only one image or the other.
 irt_nonbrowser = ['irt_interfaces.c',
                   ]
 
 irt_browser = ['irt_interfaces_ppapi.c',
                'irt_ppapi.c',
                ]
 
@@ skipping 20 matching lines @@
   # call to __nacl_read_tp, which the IRT code overrides to segregate
   # IRT-private TLS from user TLS.
   node = env.CommandTest('irt_tls_test.out',
                          ['${PYTHON}', env.File('check_tls.py'),
                           '${OBJDUMP}', irt_library])
   env.AddNodeToTestSuite(node, ['small_tests'], 'run_irt_tls_test')
   node = env.CommandTest('irt_core_tls_test.out',
                          ['${PYTHON}', env.File('check_tls.py'),
                           '${OBJDUMP}', irt_core_library])
   env.AddNodeToTestSuite(node, ['small_tests'], 'run_irt_core_tls_test')