diff --git a/Makefile b/Makefile
index b41057c56a..ca46cbd8cd 100644
--- a/Makefile
+++ b/Makefile
@@ -122,32 +122,10 @@ include $(HAVE_DOTCONFIG)
 
 include .xcompile
 
-ifeq ($(CONFIG_COMPILER_LLVM_CLANG),y)
-# FIXME: armv7/aarch64 won't build right now
-# NOTE: clang puts compiler-rt under lib/linux/libclang_rt.builtins-i386.a
-# this means the triple is i386-linux-elf instead of i386-none-elf
-CFLAGS_x86_32 = -no-integrated-as -Qunused-arguments -target i386-linux-elf -m32
-# Tone down some clang warnings
-CFLAGS_x86_32 += -Wno-unused-variable -Wno-unused-function -Wno-tautological-compare -Wno-shift-overflow
-CC_x86_32:=clang
-HOSTCC := clang
-
 ifneq ($(CONFIG_MMX),y)
 CFLAGS_x86_32 += -mno-mmx
 endif
 
-# FIXME: we end up with conflicting flags with this, not clear on this part.
-#ifneq ($(CONFIG_SSE),y)
-#CFLAGS_x86_32 += -mno-sse
-#endif
-
-CFLAGS_arm = -no-integrated-as -Qunused-arguments -target arm-eabi -ccc-gcc-name $(CC_arm)
-CC_arm:=clang
-
-CFLAGS_aarch64 = -no-integrated-as -Qunused-arguments -target aarch64-eabi -ccc-gcc-name $(CC_aarch64)
-CC_aarch64:=clang
-endif
-
 include toolchain.inc
 
 strip_quotes = $(subst ",,$(subst \",,$(1)))
diff --git a/util/xcompile/xcompile b/util/xcompile/xcompile
index 66b011a685..8b20d662f5 100755
--- a/util/xcompile/xcompile
+++ b/util/xcompile/xcompile
@@ -98,13 +98,13 @@ testas() {
 	# Architecture matched.
 	GCCPREFIX="$gccprefix"
 
-	if [ -z "$use_dash_twidth" ]; then
-		ASFLAGS=""
-		CFLAGS_GCC=""
-		LDFLAGS=""
-	else
+	unset ASFLAGS LDFLAGS
+	unset CFLAGS_GCC CFLAGS_CLANG
+
+	if [ -n "$use_dash_twidth" ]; then
 		ASFLAGS="--$twidth"
 		CFLAGS_GCC="-m$twidth"
+		CFLAGS_CLANG="-m$twidth"
 		LDFLAGS="-b $full_arch"
 
 	fi
@@ -114,6 +114,7 @@ testas() {
 		"elf32-i386" )
 			LDFLAGS="$LDFLAGS -melf_i386"
 			CFLAGS_GCC="$CFLAGS_GCC -Wl,-b,elf32-i386 -Wl,-melf_i386"
+			CFLAGS_CLANG="$CFLAGS_GCC -Wl,-b,elf32-i386 -Wl,-melf_i386"
 			;;
 	esac
 
@@ -140,6 +141,8 @@ detect_special_flags() {
 	x86)
 		testcc "$GCC"      "$CFLAGS_GCC -Wa,--divide" &&
 			CFLAGS_GCC="$CFLAGS_GCC -Wa,--divide"
+		testcc "$CLANG"      "$CFLAGS_CLANG -Wa,--divide" &&
+			CFLAGS_CLANG="$CFLAGS_CLANG -Wa,--divide"
 		# Always build for i686 -- no sse/mmx instructions since SMM
 		# modules are compiled using these flags. Note that this
 		# doesn't prevent a project using xcompile to explicitly
@@ -174,6 +177,10 @@ COMPILER_RT_${TARCH}:=${CC_RT_GCC}
 COMPILER_RT_FLAGS_${TARCH}:=${CC_RT_EXTRA_GCC}
 else
 CC_${TARCH}:=${CLANG}
+CFLAGS_${TARCH}:=${CFLAGS_CLANG}
+CFLAGS_${TARCH}+=-no-integrated-as -Qunused-arguments -m${TWIDTH}
+# tone down compiler warnings
+CFLAGS_${TARCH}+=-Wno-unused-variable -Wno-unused-function -Wno-tautological-compare -Wno-shift-overflow
 COMPILER_RT_${TARCH}:=${CC_RT_CLANG}
 COMPILER_RT_FLAGS_${TARCH}:=${CC_RT_EXTRA_CLANG}
 endif