12 Nov
2007
12 Nov
'07
3:48 p.m.
Hi
I just removed GHC 6.6.1 and installed 6.8.1, and I noticed something rather unexpected. I recompiled an existing program (with -O2), and instead of taking 30 seconds to compile, it took roughly 2 seconds.
In previous releases, certain constructs took O(n^2) time to compile. One that was a particular issue for me was: do return () return () return () Once you got to 100 return ()'s in a row GHC was totally useless, while Yhc and Hugs both had no problems. This particular problem was fixed, and I think a few others were as well - if one of those had tripped you up that may explain the speedup. Thanks Neil