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* Makefile.in (actual-all): New target, replacing the former 'all'
target.
(advice-on-failure, sanity-check): New targets.
(all): Use the new targets.
(bootstrap-all): New target, identical to 'all' but meant for the
'bootstrap' target in GNUmakefile.
(actual-bootstrap): New target, replacing the former 'bootstrap'
target.  Use the 'actual-all' target instead of the 'all' target.
(bootstrap): Use the new targets.

* GNUmakefile (bootstrap): Use the new 'bootstrap-all' target.