Is this a known bug? (GHC 6.10.x)

It's known to happen when optimising shares what shouldn't be shared. Try
compiling with -O2 -fno-cse (if that doesn't help, it doesn't necessarily
mean it's not unwanted sharing, though).
And, please, let us see some code to identify the problem.

I tried -O2 -fno-cse. No difference.

I also tried -O2 -fno-full-laziness. BIG DIFFERENCE.

The program now runs in constant space (like with -O0), but it also runs about 2x faster than -O0.

I have no idea what these switches do, but clearly one of these optimisations is actually pessimal for this particular program.

I still want to try compiling with a newer version of GHC to see what difference that makes.

(And yes, if I had the code on this PC, I could post it. It's kinda long though... In essence, it just calls randomRIO a bazillion times and writes the results into a file using hPutChar.)

_______________________________________________
Haskell-Cafe mailing list
Haskell-Cafe@haskell.org
http://www.haskell.org/mailman/listinfo/haskell-cafe

Reply via email to