> Thus, it would be interesting and important to also compare with the
> code produced by a 4.03 switch compiled without flambda.

coming right up

(different parameters, different machine, best of 5 -- it varies quite a
lot)

time (ocamlbuild -clean; ocamlbuild facs_run.native)
4.03.0	  1.36s
4.03.0+flambda
Oclassic  1.68s
O2	  2.1s
O3	  2.80s


the actual run: time ./facs_run.native

4.03.0	  23.3s
4.03.0+flambda
Oclassic  24.2s
O2	  22.7s
O3	  20.1s


so it seems compilation on flambda classic is still a bit slower than
non-flambda; as is the run time. the gains of O3 over non-flambda are
still significant, as is the difference O2 vs O3.

n