perf tools: Support static linking with libdw

The Fedora 22 version of libdw requires a couple of extra libraries to
link. With a dynamic link the dependencies are pulled in automatically,
but this doesn't work for static linking. Add the needed libraries
explicitely to the feature probe and the Makefile.

v2: Explicitly check for static linking and only add the dependencies
when -static is set. This is to avoid regressions on Arnaldo's system.

Signed-off-by: Andi Kleen <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/build/feature/Makefile

···
 test-glibc.bin:
 	$(BUILD)
 
+DWARFLIBS := -ldw
+ifeq ($(findstring -static,${LDFLAGS}),-static)
+DWARFLIBS += -lelf -lebl -lz -llzma -lbz2
+endif
+
 test-dwarf.bin:
-	$(BUILD) -ldw
+	$(BUILD) $(DWARFLIBS)
 
 test-libelf-mmap.bin:
 	$(BUILD) -lelf

tools/perf/config/Makefile

···
     else
       CFLAGS += -DHAVE_DWARF_SUPPORT $(LIBDW_CFLAGS)
       LDFLAGS += $(LIBDW_LDFLAGS)
-      EXTLIBS += -ldw
+      DWARFLIBS := -ldw
+      ifeq ($(findstring -static,${LDFLAGS}),-static)
+	DWARFLIBS += -lelf -lebl -lz -llzma -lbz2
+      endif
+      EXTLIBS += ${DWARFLIBS}
       $(call detected,CONFIG_DWARF)
     endif # PERF_HAVE_DWARF_REGS
   endif # NO_DWARF