It hasn't been tested for several year, may not even compile, has
to be linked with source code that isn't even publicly available,
and its presence was the only reason to keep some inefficient
code in gtec.cc and friends.

* iface/gspn/: Delete this directory.
* iface/Makefile.am, configure.ac, README: Adjust.
* m4/gspnlib.m4: Delete.
* src/sanity/Makefile.am: Do not use LIBGSPN_CPPFLAGS.

* src/tgbaalgos/simulation.cc: Here.

* src/sanity/style.test: Add a test.
* iface/dve2/dve2.cc, iface/dve2/dve2check.cc, src/bin/common_output.cc,
src/bin/dstar2tgba.cc, src/bin/ltl2tgba.cc, src/bin/ltlcross.cc,
src/dstarparse/dra2ba.cc, src/dstarparse/fmterror.cc,
src/dstarparse/nsa2tgba.cc, src/kripke/kripkeprint.cc,
src/kripkeparse/fmterror.cc, src/ltlast/atomic_prop.cc,
src/ltlast/bunop.cc, src/ltltest/ltlrel.cc, src/ltltest/reduc.cc,
src/ltltest/syntimpl.cc, src/ltlvisit/dotty.cc, src/ltlvisit/lbt.cc,
src/ltlvisit/randomltl.cc, src/ltlvisit/relabel.cc,
src/ltlvisit/simplify.cc, src/ltlvisit/tostring.cc, src/misc/bitvect.cc,
src/misc/optionmap.cc, src/misc/timer.cc, src/neverparse/fmterror.cc,
src/priv/freelist.cc, src/saba/sabacomplementtgba.cc,
src/sabaalgos/sabadotty.cc, src/taalgos/dotty.cc,
src/taalgos/minimize.cc, src/tgba/bdddict.cc, src/tgba/bddprint.cc,
src/tgba/futurecondcol.cc, src/tgba/taatgba.hh,
src/tgba/tgbakvcomplement.cc, src/tgba/tgbasafracomplement.cc,
src/tgbaalgos/compsusp.cc, src/tgbaalgos/cycles.cc,
src/tgbaalgos/dotty.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/emptiness.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gv04.cc,
src/tgbaalgos/lbtt.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/neverclaim.cc,
src/tgbaalgos/powerset.cc, src/tgbaalgos/replayrun.cc,
src/tgbaalgos/save.cc, src/tgbaalgos/scc.cc, src/tgbaalgos/sccfilter.cc,
src/tgbaalgos/weight.cc, src/tgbaalgos/word.cc,
src/tgbaparse/fmterror.cc, src/tgbatest/bitvect.cc,
src/tgbatest/complementation.cc, src/tgbatest/intvcmp2.cc,
src/tgbatest/intvcomp.cc, src/tgbatest/ltl2tgba.cc,
src/tgbatest/randtgba.cc: Replace << "c" by << 'c' when
appropriate.

This of course concerns push_back and push_front as well.

* src/bin/common_finput.cc, src/bin/dstar2tgba.cc, src/bin/ltl2tgba.cc,
src/bin/ltl2tgta.cc, src/bin/ltlcross.cc, src/bin/ltlfilt.cc,
src/dstarparse/dstarparse.yy, src/kripkeparse/kripkeparse.yy,
src/ltlast/formula.cc, src/ltlparse/ltlparse.yy, src/misc/minato.cc,
src/neverparse/neverclaimparse.yy, src/priv/bddalloc.cc, src/ta/ta.cc,
src/taalgos/emptinessta.cc, src/tgba/taatgba.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gtec/sccstack.cc,
src/tgbaalgos/magic.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/rundotdec.cc, src/tgbaalgos/scc.cc, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc, src/tgbaparse/tgbaparse.yy: Use emplace
to make the code less verbose and avoid creating temporaries.

* src/ltlvisit/simplify.cc, src/tgbaalgos/replayrun.cc: Here.

* src/tgbaalgos/bfssteps.cc, src/tgbaalgos/complete.cc,
src/tgbaalgos/cycles.cc, src/tgbaalgos/dtgbacomp.cc,
src/tgbaalgos/gtec/gtec.cc, src/tgbaalgos/gv04.cc,
src/tgbaalgos/isweakscc.cc, src/tgbaalgos/lbtt.cc,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/reachiter.cc,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/save.cc: Avoid calls to done().

The returned Boolean indicates whether there is a successor or not.
This way

|  for (i->first(); !i->done(); i->next())
|    {
|       ...
|    }

can be replaced by

| if (i->first()) do
|   {
|      ...
|   }
| while (i->next());

avoiding all the virtual calls to done().

* iface/dve2/dve2.cc, src/kripke/kripkeexplicit.cc,
src/kripke/kripkeexplicit.hh, src/ta/ta.hh, src/ta/taexplicit.cc,
src/ta/taexplicit.hh, src/ta/taproduct.cc, src/ta/taproduct.hh,
src/ta/tgtaproduct.cc, src/ta/tgtaproduct.hh, src/tgba/succiter.hh,
src/tgba/succiterconcrete.cc, src/tgba/succiterconcrete.hh,
src/tgba/taatgba.cc, src/tgba/taatgba.hh, src/tgba/tgba.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbamask.cc, src/tgba/tgbaproduct.cc,
src/tgba/tgbasafracomplement.cc, src/tgba/tgbasgba.cc,
src/tgba/tgbatba.cc, src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh,
src/tgba/wdbacomp.cc: Implement and adjust to this new interface.

Instead of "delete iter;" we now do "aut->release_iter(iter);" to
give the iterator back to the automaton.  The TGBA classes now
reuse a previously returned tgba_succ_iterator to answer a succ_iter()
call, therefore avoiding (1) memory allocation, as well as (2) vtable
and other constant member initialization.

* src/tgba/tgba.hh, src/tgba/tgba.cc (release_iter, iter_cache_):
Implement a release_iter() that stores the released iterator
in iter_cache_.
* src/tgba/succiter.hh (internal::succ_iterable): Move...
* src/tgba/tgba.hh (tgba::succ_iterable): ... here. And use
release_iter().

* iface/dve2/dve2.cc, src/kripke/kripke.cc, src/kripke/kripke.hh,
src/tgba/succiterconcrete.cc, src/tgba/succiterconcrete.hh,
src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.cc,
src/tgba/tgbaexplicit.hh, src/tgba/tgbamask.cc, src/tgba/tgbaproduct.cc,
src/tgba/tgbaproxy.cc, src/tgba/tgbascc.cc, src/tgba/tgbatba.cc,
src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc,
src/tgbaalgos/bfssteps.cc, src/tgbaalgos/compsusp.cc,
src/tgbaalgos/cycles.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/gtec/gtec.cc,
src/tgbaalgos/gv04.cc, src/tgbaalgos/isweakscc.cc,
src/tgbaalgos/lbtt.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/magic.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/reachiter.cc,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/scc.cc, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc: Use release_iter() instead of deleting
iterators, and used recycle iter_cache_ in implementations of
tgba::succ_iter().

| tgba_succ_iterator* i = aut->succ_iter(s);
| for (i->begin(); !i->done(); i->next())
|   {
|      // ...
|   }
| delete i;

becomes

| for (auto i: aut->succ(s))
|   {
|      // ...
|   }

hiding the begin()/done()/next() interface, taking care of the delete,
and allowing more optimization to come.

* src/tgba/succiter.hh, src/tgba/tgba.hh: Implement the above
new interface.
* iface/gspn/ssp.cc, src/dstarparse/nsa2tgba.cc,
src/saba/sabacomplementtgba.cc, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbamask.cc, src/tgba/tgbasafracomplement.cc,
src/tgba/tgbatba.cc, src/tgbaalgos/compsusp.cc, src/tgbaalgos/cutscc.cc,
src/tgbaalgos/degen.cc, src/tgbaalgos/emptiness.cc,
src/tgbaalgos/isdet.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/powerset.cc,
src/tgbaalgos/safety.cc, src/tgbaalgos/simulation.cc,
src/tgbaalgos/tau03.cc, src/tgbatest/explicit2.cc: Update for
loops.

* src/tgbaalgos/degen.cc (unicity_table): Move and rename as...
* src/tgba/state.hh (state_unicity_table): ... this.
* src/tgbaalgos/cutscc.cc, src/tgbaalgos/cycles.cc,
src/tgbaalgos/cycles.hh, src/tgbaalgos/minimize.cc,
src/tgbaalgos/powerset.cc, src/tgbaalgos/powerset.hh,
src/tgbaalgos/safety.cc: Use it to simplify existing code.

* src/ltlast/atomic_prop.cc, src/ltlast/atomic_prop.hh,
src/ltlast/automatop.cc, src/ltlast/automatop.hh, src/ltlast/binop.cc,
src/ltlast/binop.hh, src/ltlast/bunop.cc, src/ltlast/bunop.hh,
src/ltlast/multop.cc, src/ltlast/multop.hh, src/ltlast/unop.cc,
src/ltlast/unop.hh: Use std::tuple to replace nested std::pair,
simplify calls to std::map::erase, use auto and std::make_pair with
insert, and simplify the dump() method using a range for.

* src/misc/random.cc, src/misc/random.hh (srand, drand, mrand, rrand,
barand): Simplify using <random> from C++11.
(nrand, bmrand, prand): Remove these unused functions.
* src/tgbaalgos/randomgraph.cc: Adjust the use of barand.
* configure.ac: Do not check for srand48 and drand48.

The bitvect implementation seems a tad faster, but most importantly
this removes the last dependency on Boost.

* src/tgba/tgbasafracomplement.cc: Replace boost::dynamic_bitset by
spot::bitvect.

* src/misc/bitvect.hh: New method.
* src/tgbatest/bitvect.cc, src/tgbatest/bitvect.test: Test it.

* src/eltlparse/eltlparse.yy, src/ltlast/formula_tree.hh,
src/ltlast/nfa.hh, src/saba/sabastate.hh, src/tgba/state.hh: Here.

But do not replace it by std::unique_ptr, because this was not
really equivalent.

* src/misc/unique_ptr.hh: Delete.
* src/misc/Makefile.am: Adjust.
* src/tgbaalgos/simulation.cc, src/tgbatest/ltl2tgba.cc: Call
delete explicitly.

* src/misc/common.hh: Conditionally define SPOT_DELETED to = delete.
* src/ltlvisit/simplify.hh, src/ta/taexplicit.hh, src/ta/taproduct.hh,
src/tgba/bdddict.hh, src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbaproduct.hh, src/tgba/tgbasgba.hh,
src/tgba/tgbatba.hh, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc: Use
SPOT_DELETED.
* wrap/python/spot.i: Include common.hh.
* wrap/python/Makefile.am: Remove useless definition of SPOT_API
and BUDDY_API.

* src/ltlvisit/simplify.hh, src/ta/taexplicit.hh, src/ta/taproduct.hh,
src/tgba/bdddict.hh, src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbaproduct.hh, src/tgba/tgbasgba.hh,
src/tgba/tgbatba.hh, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc: Here.

* src/bin/common_finput.cc, src/bin/genltl.cc, src/bin/ltlcross.cc,
src/bin/randltl.cc: Simplify.

* bench/scc-stats/stats.cc, bench/split-product/cutscc.cc,
iface/gspn/ssp.cc, src/bin/ltlcross.cc, src/bin/ltlfilt.cc,
src/bin/randltl.cc, src/dstarparse/nsa2tgba.cc, src/ltlast/formula.hh,
src/ltlast/nfa.hh, src/ltlvisit/contain.hh, src/ltlvisit/dotty.cc,
src/ltlvisit/mark.hh, src/ltlvisit/relabel.cc, src/ltlvisit/relabel.hh,
src/ltlvisit/simplify.cc, src/ltlvisit/snf.hh, src/misc/hash.hh,
src/misc/mspool.hh, src/priv/acccompl.hh, src/priv/accconv.hh,
src/saba/explicitstateconjunction.hh, src/saba/sabastate.hh,
src/sabaalgos/sabareachiter.hh, src/sanity/style.test,
src/ta/taexplicit.cc, src/ta/taexplicit.hh, src/taalgos/emptinessta.cc,
src/taalgos/minimize.cc, src/taalgos/reachiter.hh, src/tgba/state.hh,
src/tgba/taatgba.hh, src/tgba/tgbabddconcretefactory.hh,
src/tgba/tgbaexplicit.hh, src/tgba/tgbakvcomplement.cc,
src/tgba/tgbasafracomplement.cc, src/tgba/tgbatba.cc,
src/tgba/tgbatba.hh, src/tgbaalgos/cutscc.cc, src/tgbaalgos/cycles.hh,
src/tgbaalgos/degen.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/eltl2tgba_lacim.cc,
src/tgbaalgos/emptiness.cc, src/tgbaalgos/gtec/explscc.hh,
src/tgbaalgos/gtec/nsheap.hh, src/tgbaalgos/gv04.cc,
src/tgbaalgos/ltl2tgba_fm.cc, src/tgbaalgos/magic.cc,
src/tgbaalgos/minimize.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/powerset.hh, src/tgbaalgos/randomgraph.cc,
src/tgbaalgos/reachiter.hh, src/tgbaalgos/replayrun.cc,
src/tgbaalgos/safety.cc, src/tgbaalgos/scc.hh, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc: Adjust code.
* src/sanity/style.test: Remove check.

* m4/stl.m4: Delete.
* configure.ac: Do not check for unordered_map and friends.
* src/misc/hash.hh: Remove all conditional code.

* src/ltlast/atomic_prop.cc, src/ltlast/atomic_prop.hh,
src/ltlast/automatop.cc, src/ltlast/automatop.hh, src/ltlast/binop.cc,
src/ltlast/binop.hh, src/ltlast/bunop.cc, src/ltlast/bunop.hh,
src/ltlast/constant.cc, src/ltlast/constant.hh, src/ltlast/multop.cc,
src/ltlast/multop.hh, src/ltlast/unop.cc, src/ltlast/unop.hh: Move all
one-line accessors methods like nth(), child(), op()... from *.cc files
to their respective *.hh files.

Apparently their hash tables store the hash functions in a const
member, and this requires a user-supplied default constructor.
Reported by Étienne Renault.

* src/misc/hash.hh: Add an empty constructor to all hash functions.

* src/kripke/kripkeexplicit.cc: Add missing const, reported by Etienne
Renault using Apple's clang version that is installed with OS X 10.9.

* doc/Makefile.am, src/ltltest/defs.in, src/ltltest/latex.test: Here.

* src/misc/satsolver.cc: Add the "-model" option.
* NEWS, doc/org/satmin.org, src/bin/man/spot-x.x: Mention it.

* doc/org/satmin.org, src/bin/man/spot-x.x: Document it.
* NEWS: Mention it.

* src/misc/timer.hh: Fix.
* NEWS: Mention the bug.

* src/tgbaalgos/dtbasat.cc, src/tgbaalgos/dtgbasat.cc: Record
statistics about intermediate automata if SPOT_SATLOG is set to some
filename, and display intermediate automata if SPOT_SATSHOW is set.
* bench/dtgbasat/stat.sh, bench/dtgbasat/stats.sh,
bench/dtgbasat/tabl.pl, bench/dtgbasat/tabl1.pl,
bench/dtgbasat/tabl2.pl, bench/dtgbasat/tabl3.pl,
bench/dtgbasat/tabl4.pl: Gather these extra statistics.

* src/tgbaalgos/dtbasat.cc, src/tgbaalgos/dtgbasat.cc: Compute the
actual number of reachable states in the produced automaton to prepare
the next iteration.

This was simply wrong.

* src/tgbaalgos/dtbasat.cc: reverts commit
fc5a00d24d5964d6f6a48d362ecbdec357eaf154.

* src/tgbaalgos/dtbasat.cc, src/tgbaalgos/dtgbasat.cc: More debuging
code.

* src/misc/satsolver.hh, src/misc/satsolver.cc: Present
the SAT solver as an object with a stream interface, to
prepare for a better implementation.
* src/tgbaalgos/dtbasat.cc, src/tgbaalgos/dtgbasat.cc:
Adjust to the new interface, removing all the handling
of temporary files.
* src/tgbatest/readsat.cc: Adjust.

* src/tgbaalgos/dtbasat.cc, src/tgbaalgos/dtgbasat.cc: Rewrite the
loops that number the states of the reference automaton so that
they declare CNF variable numbers in the same order as the states
of the automaton.

* src/misc/satsolver.cc: Call glucose with -verb=0.
* src/bin/man/spot-x.x: Document it.