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

tools/llvm/llvm-fake.py

Index: tools/llvm/llvm-fake.py
===================================================================
--- tools/llvm/llvm-fake.py	(revision 1957)
+++ tools/llvm/llvm-fake.py	(working copy)
@@ -24,7 +24,7 @@
 # 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')
@@ -49,10 +49,10 @@
 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
@@ -184,8 +184,8 @@
 
 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'
 
@@ -215,7 +215,10 @@
 # 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
@@ -556,8 +559,10 @@
   #       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
@@ -623,6 +628,10 @@
   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])