Remove _Unwind_* stubs from pnacl_abi.bc

pnacl/driver/pnacl-ld.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.
 #
 # IMPORTANT NOTE: If you make local mods to this file, you must run:
 #   %  pnacl/build.sh driver
 # in order for them to take effect in the scons build.  This command
 # updates the copy in the toolchain/ tree.
 #
@@ skipping 83 matching lines @@
   'LIBS_X8664'       : '${BASE_GLIBC}/lib-x86-64',
   'LIBS_MIPS32'      : '${BASE_GLIBC}/lib-mips32',
   # HACK-END
 
   'LD_GOLD_OFORMAT'        : '${LD_GOLD_OFORMAT_%ARCH%}',
   'LD_GOLD_OFORMAT_ARM'    : 'elf32-littlearm',
   'LD_GOLD_OFORMAT_X8632'  : 'elf32-i386-nacl',
   'LD_GOLD_OFORMAT_X8664'  : 'elf64-x86-64-nacl',
   'LD_GOLD_OFORMAT_MIPS32' : 'elf32-tradlittlemips',
 
-  'BCLD'      : '${LD_GOLD}',
-  'BCLD_FLAGS': '--oformat ${LD_GOLD_OFORMAT} -Ttext=0x20000 ' +
-                '${!SHARED && !RELOCATABLE ? --undef-sym-check} ' +
-                '${GOLD_PLUGIN_ARGS} ${LD_FLAGS}',
+  'BCLD'                   : '${LD_GOLD}',
+  'BCLD_ALLOW_UNRESOLVED'  :
+    '${ALLOW_CXX_EXCEPTIONS ? '
+      '--allow-unresolved=_Unwind_Backtrace '
+      '--allow-unresolved=_Unwind_DeleteException '
+      '--allow-unresolved=_Unwind_GetCFA '
+      '--allow-unresolved=_Unwind_GetDataRelBase '
+      '--allow-unresolved=_Unwind_GetIP '
+      '--allow-unresolved=_Unwind_GetIPInfo '
+      '--allow-unresolved=_Unwind_GetLanguageSpecificData '
+      '--allow-unresolved=_Unwind_GetRegionStart '
+      '--allow-unresolved=_Unwind_GetTextRelBase '
+      '--allow-unresolved=_Unwind_PNaClSetResult0 '
+      '--allow-unresolved=_Unwind_PNaClSetResult1 '
+      '--allow-unresolved=_Unwind_RaiseException '
+      '--allow-unresolved=_Unwind_Resume '
+      '--allow-unresolved=_Unwind_Resume_or_Rethrow '
+      '--allow-unresolved=_Unwind_SetIP}',
+
+  'BCLD_FLAGS':
+    '--oformat ${LD_GOLD_OFORMAT} -Ttext=0x20000 ' +
+    '${!SHARED && !RELOCATABLE ? --undef-sym-check ${BCLD_ALLOW_UNRESOLVED}} ' +
+    '${GOLD_PLUGIN_ARGS} ${LD_FLAGS}',
   'RUN_BCLD': ('${BCLD} ${BCLD_FLAGS} ${inputs} -o ${output}'),
 
   'ALLOW_CXX_EXCEPTIONS': '0',
   'DISABLE_ABI_CHECK': '0',
   'LLVM_PASSES_TO_DISABLE': '',
 }
 
 def AddToBCLinkFlags(*args):
   env.append('LD_FLAGS', *args)
 
@@ skipping 424 matching lines @@
   -O<opt-level>               Optimize output file
   -M, --print-map             Print map file on standard output
   --whole-archive             Include all objects from following archives
   --no-whole-archive          Turn off --whole-archive
   -s, --strip-all             Strip all symbols
   -S, --strip-debug           Strip debugging symbols
   --undefined SYMBOL          Start with undefined reference to SYMBOL
 
   -help | -h                  Output this help.
 """