Merge branch 'sg/make-fix-ar-invocation'

Build fix.

* sg/make-fix-ar-invocation:
  Makefile: remove archives before manipulating them with 'ar'

Author: gitster

Makefile

@@ -2607,10 +2607,10 @@ $(REMOTE_CURL_PRIMARY): remote-curl.o http.o http-walker.o GIT-LDFLAGS $(GITLIBS
 		$(CURL_LIBCURL) $(EXPAT_LIBEXPAT) $(LIBS)
 
 $(LIB_FILE): $(LIB_OBJS)
-	$(QUIET_AR)$(AR) $(ARFLAGS) $@ $^
+	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
 
 $(XDIFF_LIB): $(XDIFF_OBJS)
-	$(QUIET_AR)$(AR) $(ARFLAGS) $@ $^
+	$(QUIET_AR)$(RM) $@ && $(AR) $(ARFLAGS) $@ $^
 
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