Fix makefile to use chrome clang to compile, so we link to LLVM.

Makefile.standalone

 # The following variables will likely need to be modified, depending on where
 # and how you built LLVM & Clang. They can be overridden in a command-line
 # invocation of make, like:
 #
-#   make LLVM_SRC_PATH=<path> LLVM_BIN_PATH=<path> ...
+#   make LLVM_SRC_PATH=<path> LLVM_BIN_PATH=<path> \
+#        LIBCXX_INSTALL_PATH=<path> CLANG_PATH=<path> ...
 #
 
 # LLVM_SRC_PATH is the path to the root of the checked out source code. This
 # directory should contain the configure script, the include/ and lib/
 # directories of LLVM, Clang in tools/clang/, etc.
 # Alternatively, if you're building vs. a binary download of LLVM, then
 # LLVM_SRC_PATH can point to the main untarred directory.
 LLVM_SRC_PATH ?= ../llvm
 
 # LLVM_BIN_PATH is the directory where binaries are placed by the LLVM build
 # process. It should contain the tools like opt, llc and clang. The default
 # reflects a debug build with autotools (configure & make).
 LLVM_BIN_PATH ?= $(shell readlink -e \
         ../../out/llvm_i686_linux_work/Release+Asserts/bin)
 
+# LIBCXX_INSTALL_PATH is the directory where libc++ is located. It should
+# contain header files and corresponding libraries
+LIBCXX_INSTALL_PATH ?= $(shell readlink -e \
+        ../../../toolchain/linux_x86/pnacl_newlib/host_x86_32)
+
+# CLANG_PATH is the location of the clang compiler to use.
+CLANG_PATH ?= $(shell readlink -e \
+        ../../../../third_party/llvm-build/Release+Asserts/bin)
+
 HOST_ARCH ?= x86
 ifeq ($(HOST_ARCH),x86_64)
-  HOST_FLAGS = -m64
+  HOST_FLAGS = -m64 -stdlib=libc++
 else
   ifeq ($(HOST_ARCH),x86)
-    HOST_FLAGS = -m32
+    HOST_FLAGS = -m32 -stdlib=libc++
   endif
 endif
 
 $(info -----------------------------------------------)
 $(info Using LLVM_SRC_PATH = $(LLVM_SRC_PATH))
 $(info Using LLVM_BIN_PATH = $(LLVM_BIN_PATH))
+$(info Using LIBCXX_INSTALL_PATH = $(LIBCXX_INSTALL_PATH))
+$(info Using CLANG_PATH = $(CLANG_PATH))
 $(info Using HOST_ARCH     = $(HOST_ARCH))
 $(info -----------------------------------------------)
 
 LLVM_CXXFLAGS := `$(LLVM_BIN_PATH)/llvm-config --cxxflags`
 LLVM_LDFLAGS := `$(LLVM_BIN_PATH)/llvm-config --libs` \
                 `$(LLVM_BIN_PATH)/llvm-config --ldflags`
 
 # It's recommended that CXX matches the compiler you used to build LLVM itself.
 OPTLEVEL := -O0
-CXX := g++
+CXX := $(CLANG_PATH)/clang++
 
 CXXFLAGS := $(LLVM_CXXFLAGS) -Wall -Wextra -Werror -fno-rtti \
         -fno-exceptions $(OPTLEVEL) -g $(HOST_FLAGS) \
-        -Wno-error=unused-parameter
-LDFLAGS := $(HOST_FLAGS)
+        -Wno-error=unused-parameter -I$(LIBCXX_INSTALL_PATH)/include/c++/v1
+LDFLAGS := $(HOST_FLAGS) -L$(LIBCXX_INSTALL_PATH)/lib
 
 SRCS= \
         IceCfg.cpp \
         IceCfgNode.cpp \
         IceConverter.cpp \
         IceGlobalContext.cpp \
         IceInst.cpp \
         IceInstX8632.cpp \
         IceIntrinsics.cpp \
         IceLiveness.cpp \
         IceOperand.cpp \
         IceRegAlloc.cpp \
         IceRNG.cpp \
         IceTargetLowering.cpp \
         IceTargetLoweringX8632.cpp \
         IceTranslator.cpp \
         IceTypeConverter.cpp \
         IceTypes.cpp \
         llvm2ice.cpp \
         PNaClTranslator.cpp
 
 OBJS=$(patsubst %.cpp, build/%.o, $(SRCS))
 
 # Keep all the first target so it's the default.
 all: llvm2ice
 
 .PHONY: all
 
 llvm2ice: $(OBJS)
-        $(CXX) $(LDFLAGS) -o $@ $^ $(LLVM_LDFLAGS) -ldl
+        $(CXX) $(LDFLAGS) -o $@ $^ $(LLVM_LDFLAGS) -ldl \
+               -Wl,-rpath=$(abspath $(LIBCXX_INSTALL_PATH)/lib)
 
 # TODO: Be more precise than "*.h" here and elsewhere.
 $(OBJS): build/%.o: src/%.cpp src/*.h src/*.def
         $(CXX) -c $(CXXFLAGS) $< -o $@
 
 $(OBJS): | build
 
 build:
         @mkdir -p $@
 
@@ skipping 18 matching lines @@
   CLANG_FORMAT_DIFF = clang-format-diff.py
 else
   CLANG_FORMAT_DIFF = /usr/lib/clang-format/clang-format-diff.py
 endif
 format-diff:
         git diff -U0 `git merge-base HEAD master` | \
         $(CLANG_FORMAT_DIFF) -p1 -style=LLVM -i
 
 clean:
         rm -rf llvm2ice *.o build/