Add ARM toolchain support.

Makefile

 # 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.
 #
 # Makefile
 #
 # usage: 'make [package]'
 #
 # This makefile builds all of the Native Client packages listed below
 # in $(PACKAGES). Each package has a dependency on its own sentinel
@@ skipping 12 matching lines @@
   OS_SUBDIR := linux
 endif
 ifneq (, $(filter CYGWIN%,$(OS_NAME)))
   OS_SUBDIR := win
 endif
 
 ifeq ($(OS_SUBDIR), UNKNOWN)
   $(error No support for the Operating System: $(OS_NAME))
 endif
 
+ifndef NACL_ARCH
+   NACL_ARCH := i686
+endif
+
 ifndef NACL_SDK_ROOT
   $(error NACL_SDK_ROOT not set, see README.txt)
 endif
 
+ifeq ($(NACL_ARCH), "ARM")
+  NACL_TOOLCHAIN_ROOT = $(NACL_SDK_ROOT)/toolchain/$(OS_SUBDIR)_arm_newlib
+else
 ifeq ($(NACL_GLIBC), 1)
   NACL_TOOLCHAIN_ROOT = $(NACL_SDK_ROOT)/toolchain/$(OS_SUBDIR)_x86_glibc
   NACL_LIBC = glibc
 else
   NACL_TOOLCHAIN_ROOT = $(NACL_SDK_ROOT)/toolchain/$(OS_SUBDIR)_x86_newlib
   NACL_LIBC = newlib
 endif
+endif
 
 NACL_OUT = out
 NACL_DIRS_BASE = $(NACL_OUT)/tarballs \
-                 $(NACL_OUT)/repository-i686 \
-                 $(NACL_OUT)/repository-x86_64 \
+                 $(NACL_OUT)/repository-$(NACL_ARCH) \
                  $(NACL_OUT)/publish
 
-NACL_SDK_USR32 = $(NACL_TOOLCHAIN_ROOT)/i686-nacl/usr
-NACL_SDK_USR64 = $(NACL_TOOLCHAIN_ROOT)/x86_64-nacl/usr
+NACL_SDK_USR = $(NACL_TOOLCHAIN_ROOT)/$(NACL_ARCH)-nacl/usr
 
 NACL_DIRS_TO_REMOVE = $(NACL_OUT) \
-                      $(NACL_SDK_USR32) \
-                      $(NACL_SDK_USR64)
+                      $(NACL_SDK_USR) \
 
 NACL_DIRS_TO_MAKE = $(NACL_DIRS_BASE) \
-                    $(NACL_SDK_USR32)/include \
-                    $(NACL_SDK_USR64)/include \
-                    $(NACL_SDK_USR32)/lib \
-                    $(NACL_SDK_USR64)/lib
+                    $(NACL_SDK_USR)/include \
+                    $(NACL_SDK_USR)/lib
 
 LIBRARIES = \
      libraries/nacl-mounts \
      libraries/SDL-1.2.14 \
      libraries/SDL_mixer-1.2.11 \
      libraries/SDL_image-1.2.10 \
      libraries/SDL_ttf-2.0.10 \
      libraries/gc6.8 \
      libraries/fftw-3.2.2 \
      libraries/libtommath-0.41 \
@@ skipping 62 matching lines @@
 endif
 
 ifeq ($(OS_NAME), Linux)
   LIBRARIES += libraries/openssl-1.0.0e
 endif
 
 PACKAGES = $(LIBRARIES) $(EXAMPLES)
 
 
 SENTINELS_DIR = $(NACL_OUT)/sentinels
-SENT = $(SENTINELS_DIR)/bits$(NACL_PACKAGES_BITSIZE)_$(NACL_LIBC)
+SENT = $(SENTINELS_DIR)/$(NACL_ARCH)_$(NACL_LIBC)
 
 default: libraries
 libraries: $(LIBRARIES)
 examples: $(EXAMPLES)
 all: $(PACKAGES)
 
 .PHONY: all default libraries examples clean
 
 
 clean:
         rm -rf $(NACL_DIRS_TO_REMOVE)
 
 $(NACL_DIRS_TO_MAKE):
         mkdir -p $@
 
 $(PACKAGES): %: $(NACL_DIRS_TO_MAKE) $(SENT)/%
 
 $(PACKAGES:%=$(SENT)/%): $(SENT)/%:
-        @echo "@@@BUILD_STEP $(NACL_PACKAGES_BITSIZE)-bit $(notdir $*)@@@"
+        @echo "@@@BUILD_STEP $(NACL_ARCH) $(notdir $*)@@@"
         cd $* && ./nacl-$(notdir $*).sh
         mkdir -p $(@D)
         touch $@
 
 # packages with dependencies
 $(SENT)/libraries/libvorbis-1.2.3: libraries/libogg-1.1.4
 $(SENT)/libraries/libtheora-1.1.1: libraries/libogg-1.1.4
 $(SENT)/libraries/flac-1.2.1: libraries/libogg-1.1.4
 $(SENT)/libraries/speex-1.2rc1: libraries/libogg-1.1.4
 $(SENT)/libraries/fontconfig-2.7.3: libraries/expat-2.0.1 \
@@ skipping 107 matching lines @@
 # PNACL
 ######################################################################
 # Libraries and Examples should work for PNaCl, but if new examples
 # do not work, you can filter them here.
 WORKS_FOR_PNACL=$(LIBRARIES) $(EXAMPLES)
 
 works_for_pnacl: $(WORKS_FOR_PNACL)
 
 works_for_pnacl_list:
         @echo $(WORKS_FOR_PNACL)