Issue a warning if naclsdk_mode=manual is specified with ARM.

tools/llvm/llvm-fake.py

 #!/usr/bin/python
 # Copyright 2009 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.
 
 # this script is a replacement for llvm-gcc and llvm-g++ driver.
 # It detects automatically which role it is supposed to assume.
 # The point of the script is to redirect builds through our own tools,
 # while making these tools appear like gnu tools.
 #
 # Compared to the gcc driver the usage patterns of this script
 # are somewhat restricted:
 # * you cannot compile and link at the same time
 # * you cannot specify multiple source files in one invocation
 # * ...
 #
 
 
 import os
 import struct
 import subprocess
 import sys
 
 # enable this for manual debugging of this script only
 # NOTE: this HAS to be zero in order to work with the llvm-gcc
 #       bootstrapping process
-VERBOSE = 0
+VERBOSE = 1
 TOLERATE_COMPILATION_OF_ASM_CODE = 1
 # NOTE: set this to something like:
 OUT = open('/tmp/fake.log', 'a')
 # if you want a log of all the action. otherwise:
 #OUT = None
 
 ######################################################################
 # Misc
 ######################################################################
 
 BASE = os.path.dirname(os.path.dirname(sys.argv[0]))
 
 LD_SCRIPT_ARM = BASE + '/arm-none-linux-gnueabi/ld_script_arm_untrusted'
 
 # TODO(robertm) clean this up
 LD_SCRIPT_X8632 = BASE + '/../../tools/llvm/ld_script_x86_untrusted'
 
 # arm libgcc
 LIBDIR_ARM_1 = BASE + '/armsfi-lib'
 
 # arm startup code + libs (+ bitcode when in bitcode mode)
 LIBDIR_ARM_2 = BASE + '/arm-newlib/arm-none-linux-gnueabi/lib'
 
 # x86 libgcc
-LIBDIR_X8632_1 = BASE + '/../linux_x86/sdk/nacl-sdk/nacl64/lib/32'
+LIBDIR_X8632_2 = BASE + '/../linux_x86/sdk/nacl-sdk/nacl64/lib/32'
 
 # x86 startup code
-LIBDIR_X8632_2 = BASE + '/../linux_x86/sdk/nacl-sdk/lib/gcc/nacl64/4.4.3/32/'
+LIBDIR_X8632_1 = BASE + '/../linux_x86/sdk/nacl-sdk/lib/gcc/nacl64/4.4.3/32/'
 
 # NOTE: ugly work around for some llvm-ld shortcomings:
 #       we need to keep some symbols alive which are referenced by
 #       native code libraries linked in at the very end
 REACHABLE_FUNCTION_SYMBOLS = LIBDIR_ARM_2 + '/reachable_function_symbols.o'
 
 # Note: this works around an assembler bug that has been fixed only recently
 # We probably can drop this once we have switched to codesourcery 2009Q4
 HACK_ASM = ['sed', '-e', 's/vmrs.*apsr_nzcv, fpscr/fmrx r15, fpscr/g']
 
@@ skipping 111 matching lines @@
 ######################################################################
 
 LLVM_GCC = BASE + '/arm-none-linux-gnueabi/llvm-gcc-4.2/bin/llvm-gcc'
 
 LLVM_GXX = BASE + '/arm-none-linux-gnueabi/llvm-gcc-4.2/bin/llvm-g++'
 
 LLC_ARM = BASE + '/arm-none-linux-gnueabi/llvm/bin/llc'
 
 LLC_SFI_ARM = BASE + '/arm-none-linux-gnueabi/llvm/bin/llc-sfi'
 
-# NOTE: patch your own llc in here
-LLC_SFI_X86 = None
+# Path to llc executable for x86-32.
+LLC_SFI_X86 = os.getenv('LLC_SFI_X86', None)
 
 LLVM_LINK = BASE + '/arm-none-linux-gnueabi/llvm/bin/llvm-link'
 
 LLVM_LD = BASE + '/arm-none-linux-gnueabi/llvm/bin/llvm-ld'
 
 OPT = BASE + '/arm-none-linux-gnueabi/llvm/bin/opt'
 
 # NOTE: from code sourcery
 AS_ARM = BASE + '/codesourcery/arm-2007q3/arm-none-linux-gnueabi/bin/as'
 
 # NOTE: hack, assuming presence of x86/32 toolchain expected
 # TODO(robertm): clean this up
 AS_X8632 = BASE + '/../linux_x86/sdk/nacl-sdk/bin/nacl64-as'
 
 # NOTE: from code sourcery
 # TODO(robertm): get rid of the use of gcc here this uses cpp + as
 CCAS_ARM = BASE + '/codesourcery/arm-2007q3/arm-none-linux-gnueabi/bin/gcc'
 
 # NOTE: hack, assuming presence of x86/32 toolchain expected
 # TODO(robertm): clean this up
 CCAS_X8632 = BASE + '/../linux_x86-32/sdk/nacl-sdk/bin/nacl-gcc'
 
 LD_ARM = BASE + '/codesourcery/arm-2007q3/arm-none-linux-gnueabi/bin/ld'
 
 # NOTE: hack, assuming presence of x86/32 toolchain expected
 # TODO(robertm): clean this up - we may not need separate linkers
 # NOTE(robertm): the nacl linker sometimes creates empty sections like .plt
 #                so we use the system linker for now
 #LD_X8632 = BASE + '/../linux_x86-32/sdk/nacl-sdk/bin/nacl-ld'
-LD_X8632 = 'ld'
+LD_X8632 = '/usr/bin/ld'
+# NOTE(adonovan): this should _not_ be the Gold linker, e.g. 2.18.*.
+# Beware, one of the Chrome installation scripts may have changed
+# /usr/bin/ld (which is evil).
 
 ######################################################################
 # Code
 ######################################################################
 
 def LogInfo(m):
   if VERBOSE:
     print m
   if OUT:
     print >> OUT, m
@@ skipping 320 matching lines @@
       LogFatal('Unexpected ld arg: %s' % a)
 
   assert output
 
   # NOTE: LLVM_LD automagically appends .bc to the output
   # NOTE: without -disable-internalize only the symbol 'main'
   #       is exported, but we need some more for the startup code
   #       which kept alive via REACHABLE_FUNCTION_SYMBOLS
   if '-nostdlib' not in argv:
     if last_bitcode_pos != None:
+      # Splice in the extra symbols.
+      # TODO(adonovan): temp hack to avoid "multiple defns" error.
       args_bit_ld = (args_bit_ld[:last_bitcode_pos] +
-                     [REACHABLE_FUNCTION_SYMBOLS] +
+#                    [REACHABLE_FUNCTION_SYMBOLS] +
                      args_bit_ld[last_bitcode_pos:])
 
   # NOTE: .bc will be appended output by LLVM_LD
   Run([LLVM_LD] + args_bit_ld + ['-disable-internalize', '-o', output])
   return output, args_native_ld
 
 
 def Incarnation_bcldarm(argv):
   """The ld step for bitcode is quite elaborate:
      1) Run llvm-ld to produce a single bitcode file
@@ skipping 45 matching lines @@
 
      TODO(robertm): llvm-ld does NOT complain when passed a native .o file.
                     It will discard it silently.
   """
   output, args_native_ld = GenerateCombinedBitcodeFile(argv)
 
   bitcode_combined = output + ".bc"
   asm_combined = output + ".bc.s"
   obj_combined = output + ".bc.o"
 
+  # TODO(adonovan): use external env var until we complete llc SFI for x86.
+  if not LLC_SFI_X86:
+    LogFatal('You must set LLC_SFI_X86 to your llc executable for x86-32.')
+
   Run([LLC_SFI_X86] +
       LLC_SHARED_FLAGS_X8632 +
       ['-f', bitcode_combined, '-o', asm_combined])
 
   Run([AS_X8632] + AS_FLAGS_X8632 + [asm_combined, '-o', obj_combined])
 
   args_native_ld = MassageFinalLinkCommandX8632([obj_combined] + args_native_ld)
 
   Run([LD_X8632] +  args_native_ld)
 
@@ skipping 46 matching lines @@
   if basename not in INCARNATIONS:
     LogFatal("unknown command: " + StringifyCommand(argv))
 
 
   INCARNATIONS[basename](argv)
   return 0
 
 
 if __name__ == "__main__":
   sys.exit(main(sys.argv))