[NaCL SDK] Add initial support for nacl-clang

native_client_sdk/src/tools/nacl_gcc.mk

Index: native_client_sdk/src/tools/nacl_gcc.mk
diff --git a/native_client_sdk/src/tools/nacl_gcc.mk b/native_client_sdk/src/tools/nacl_gcc.mk
index 1b0d984d48389161cddd456e91b4ce7151bca52d..37fb448bd0f211d0389447a161704c435aecd57e 100644
--- a/native_client_sdk/src/tools/nacl_gcc.mk
+++ b/native_client_sdk/src/tools/nacl_gcc.mk
@@ -26,7 +26,11 @@ X86_64_STRIP := $(shell $(NACL_CONFIG) -t $(TOOLCHAIN) -a x86_64 --tool=strip)
 X86_64_NM := $(shell $(NACL_CONFIG) -t $(TOOLCHAIN) -a x86_64 --tool=nm)
 endif
 
-ifeq (,$(findstring $(TOOLCHAIN),glibc))
+ifneq (,$(findstring $(TOOLCHAIN),newlib bionic))
+ARM_SUPPORT=1
+endif
+
+ifeq ($(ARM_SUPPORT),1)
 ARM_CC := $(NACL_COMPILER_PREFIX) $(shell $(NACL_CONFIG) -t $(TOOLCHAIN) -a arm --tool=cc)
 ARM_CXX := $(NACL_COMPILER_PREFIX) $(shell $(NACL_CONFIG) -t $(TOOLCHAIN) -a arm --tool=c++)
 ARM_LINK := $(shell $(NACL_CONFIG) -t $(TOOLCHAIN) -a arm --tool=c++)
@@ -179,7 +183,7 @@ endef
 ifneq ($(TOOLCHAIN),bionic)
 VALID_ARCHES := x86_32 x86_64
 endif
-ifneq (glibc,$(TOOLCHAIN))
+ifeq ($(ARM_SUPPORT),1)
 VALID_ARCHES += arm
 endif
 
@@ -319,7 +323,7 @@ $(LIBDIR)/$(TOOLCHAIN)_x86_64/$(CONFIG)/lib$(1).a: $(X86_64_OUTDIR)/lib$(1)_x86_
 endif
 
 ifneq (,$(findstring arm,$(ARCHES)))
-ifneq ($(TOOLCHAIN),glibc)
+ifeq ($(ARM_SUPPORT),1)
 all: $(ARM_OUTDIR)/lib$(1)_arm.a
 $(ARM_OUTDIR)/lib$(1)_arm.a: $(foreach src,$(2),$(call SRC_TO_OBJ,$(src),_arm))
 	$(MKDIR) -p $$(dir $$@)