multiarch: introduced the multiarch support into the build system.

* The linker script pie/pie.lds.S is generated from the template
  pie/pie.lds.S.in by prepending the output architecture specification.
  The output architecture is defined by the variable LDARCH.

* Blobs are generated by objcopy instead of ld because the ARM linker
  fails to produce a binary when supplied a script.
  (See http://lists.gnu.org/archive/html/bug-binutils/2008-10/msg00091.html).
Signed-off-by: Alexander Kartashov <alekskartashov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

Makefile

@@ -22,6 +22,7 @@ NM		:= nm
 AWK		:= awk
 SH		:= sh
 MAKE		:= make
+OBJCOPY		:= objcopy
 
 # Additional ARCH settings for x86
 ARCH ?= $(shell echo $(uname_M) | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
@@ -38,6 +39,7 @@ endif
 ifeq ($(uname_M),x86_64)
 	ARCH         := x86
 	DEFINES      := -DCONFIG_X86_64
+	LDARCH       := i386:x86-64
 endif
 
 SRC_DIR		?= $(shell pwd)
@@ -71,7 +73,7 @@ CFLAGS		+= $(WARNINGS) $(DEFINES)
 SYSCALL-LIB	= $(SRC_DIR)/arch/$(ARCH)/syscalls.o
 PROTOBUF-LIB	= $(SRC_DIR)/protobuf/protobuf-lib.o
 
-export E Q CC ECHO MAKE CFLAGS LIBS ARCH DEFINES MAKEFLAGS SRC_DIR SYSCALL-LIB SH ARCH_DIR
+export E Q CC ECHO MAKE CFLAGS LIBS ARCH DEFINES MAKEFLAGS SRC_DIR SYSCALL-LIB SH ARCH_DIR OBJCOPY LDARCH
 
 
 PROGRAM		:= crtools
@@ -123,7 +125,7 @@ OBJS		+= cpu.o
 DEPS		:= $(patsubst %.o,%.d,$(OBJS))
 
 .PHONY: all zdtm test rebuild clean distclean tags cscope	\
-	docs help pie protobuf x86
+	docs help pie protobuf $(ARCH)
 
 ifeq ($(GCOV),1)
 %.o $(PROGRAM): override CFLAGS += --coverage
@@ -138,8 +140,8 @@ pie: protobuf $(ARCH)
 protobuf:
 	$(Q) $(MAKE) -C protobuf/
 
-x86:
-	$(Q) $(MAKE) -C arch/x86/
+$(ARCH):
+	$(Q) $(MAKE) -C arch/$(ARCH)/
 
 %.o: %.c
 	$(E) "  CC      " $@
@@ -188,7 +190,7 @@ clean:
 	$(Q) $(RM) -f ./*.gcov ./*.gcda ./*.gcno
 	$(Q) $(RM) -rf ./gcov
 	$(Q) $(MAKE) -C protobuf/ clean
-	$(Q) $(MAKE) -C arch/x86/ clean
+	$(Q) $(MAKE) -C arch/$(ARCH)/ clean
 	$(Q) $(MAKE) -C pie/ clean
 	$(Q) $(MAKE) -C test/zdtm cleandep
 	$(Q) $(MAKE) -C test/zdtm clean

pie/Makefile

@@ -18,6 +18,11 @@ LIB-OBJS	= log-simple.o blob-util-net.o $(SYSCALL-LIB)
 $(PARASITE): $(LIB-OBJS) $(PASM-OBJS) $(PIELDS)
 $(RESTORER): $(LIB-OBJS) $(PIELDS)
 
+$(PIELDS): $(PIELDS).in
+	$(E) "  GEN     " $@
+	$(Q) $(SH) -c "echo 'OUTPUT_ARCH($(LDARCH))' > $(PIELDS)"
+	$(Q) $(SH) -c "cat $(PIELDS).in >> $(PIELDS)"
+
 blob-util-net.o: $(SRC_DIR)/util-net.c
 	$(E) "  CC      " $@
 	$(Q) $(CC) $(CFLAGS) $< -o $@
@@ -32,11 +37,11 @@ blob-util-net.o: $(SRC_DIR)/util-net.c
 
 %.bin.o: %.o
 	$(E) "  GEN     " $@
-	$(Q) $(LD) --oformat=elf64-x86-64 -T $(PIELDS) -o $@ $(^:$(PIELDS)=)
+	$(Q) $(LD) -T $(PIELDS) -o $@ $(^:$(PIELDS)=)
 
-%.bin: %.o
+%.bin: %.bin.o
 	$(E) "  GEN     " $@
-	$(Q) $(LD) --oformat=binary -T $(PIELDS) -o $@ $(^:$(PIELDS)=)
+	$(Q) $(OBJCOPY) -O binary $< $@
 
 %-blob.h: %.bin %.bin.o $(GEN-OFFSETS)
 	$(E) "  GEN     " $@
@@ -51,6 +56,7 @@ clean:
 	$(Q) $(RM) -f ./*.d
 	$(Q) $(RM) -f ./*.bin
 	$(Q) $(RM) -f ./*.bin.o
+	$(Q) $(RM) -f $(PIELDS)
 
 .PHONY: clean pie
 .SECONDARY:

pie/pie.lds.S → pie/pie.lds.S.in

-OUTPUT_ARCH(i386:x86-64)
-
 SECTIONS
 {
 	.crblob 0x0 : {