llvm-gcc-4.2/gcc/config/t-libunwind-elf

# Build libunwind for ELF with the GNU linker.

# Use unwind-dw2-fde-glibc
LIBUNWIND = $(srcdir)/unwind-dw2.c $(srcdir)/unwind-dw2-fde-glibc.c
LIBUNWINDDEP = unwind.inc unwind-dw2-fde.h unwind-dw2-fde.c

SHLIBUNWIND_SOVERSION = 7
SHLIBUNWIND_SONAME = @shlib_base_name@.so.$(SHLIBUNWIND_SOVERSION)

SHLIBUNWIND_LINK = $(GCC_FOR_TARGET) $(LIBGCC2_CFLAGS) -shared \
	-nodefaultlibs -Wl,-h,$(SHLIBUNWIND_SONAME) \
	-Wl,-z,text -Wl,-z,defs -o $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME).tmp \
	@multilib_flags@ $(SHLIB_OBJS) -lc && \
	rm -f $(SHLIB_DIR)/$(SHLIB_SOLINK) && \
	if [ -f $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME) ]; then \
	  mv -f $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME) \
		$(SHLIB_DIR)/$(SHLIBUNWIND_SONAME).backup; \
	else true; fi && \
	mv $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME).tmp \
	   $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME) && \
	$(LN_S) $(SHLIBUNWIND_SONAME) $(SHLIB_DIR)/$(SHLIB_SOLINK)

# $(slibdir) double quoted to protect it from expansion while building
# libgcc.mk.  We want this delayed until actual install time.
SHLIBUNWIND_INSTALL = \
	$$(SHELL) $$(srcdir)/mkinstalldirs $$(DESTDIR)$$(slibdir)$(SHLIB_SLIBDIR_QUAL); \
	$(INSTALL_DATA) $(SHLIB_DIR)/$(SHLIBUNWIND_SONAME) \
	  $$(DESTDIR)$$(slibdir)$(SHLIB_SLIBDIR_QUAL)/$(SHLIBUNWIND_SONAME); \
	rm -f $$(DESTDIR)$$(slibdir)$(SHLIB_SLIBDIR_QUAL)/$(SHLIB_SOLINK); \
	$(LN_S) $(SHLIBUNWIND_SONAME) \
	  $$(DESTDIR)$$(slibdir)$(SHLIB_SLIBDIR_QUAL)/$(SHLIB_SOLINK)