Merge branch 'lt/diffgen' into next

* lt/diffgen:
  add clean and ignore rules for xdiff/
  Remove dependency on a file named "-lz"

.gitignore

@@ -128,8 +128,7 @@ common-cmds.h
 *.deb
 git-core.spec
 *.exe
-libgit.a
-*.o
+*.[ao]
 *.py[co]
 config.mak
 git-blame

Makefile

@@ -210,8 +210,8 @@ LIB_OBJS = \
 	fetch-clone.o revision.o pager.o \
 	$(DIFF_OBJS)
 
-LIBS = $(LIB_FILE) $(XDIFF_LIB)
-LIBS += -lz
+GITLIBS = $(LIB_FILE) $(XDIFF_LIB)
+LIBS = $(GITLIBS) -lz
 
 #
 # Platform specific tweaks
@@ -545,7 +545,7 @@ init-db.o: init-db.c
 		-DDEFAULT_GIT_TEMPLATE_DIR='"$(template_dir_SQ)"' $*.c
 
 $(LIB_OBJS): $(LIB_H)
-$(patsubst git-%$X,%.o,$(PROGRAMS)): $(LIBS)
+$(patsubst git-%$X,%.o,$(PROGRAMS)): $(GITLIBS)
 $(DIFF_OBJS): diffcore.h
 
 $(LIB_FILE): $(LIB_OBJS)
@@ -629,7 +629,8 @@ rpm: dist
 ### Cleaning rules
 
 clean:
-	rm -f *.o mozilla-sha1/*.o arm/*.o ppc/*.o compat/*.o $(LIB_FILE)
+	rm -f *.o mozilla-sha1/*.o arm/*.o ppc/*.o compat/*.o xdiff/*.o \
+		$(LIB_FILE) $(XDIFF_LIB)
 	rm -f $(ALL_PROGRAMS) git$X
 	rm -f *.spec *.pyc *.pyo */*.pyc */*.pyo common-cmds.h TAGS tags
 	rm -rf $(GIT_TARNAME)