Re: slight difference in strictness between -O0 and -O

On 3/12/07, Kirsten Chevalier wrote:

On 3/12/07, Albert Y. C. Lai wrote:

...

main = print (map (const 'x') (take 1 (undefined:undefined)))

In ghci, or with ghc -O0, this produces "x". With ghc -O, this produces Prelude.undefined.

What version of ghc?

I was curious, so I checked this against ghc 6.6. Indeed, it exhibits the behavior Albert describes above. Same goes for the HEAD. In ghc 6.4.2, however, the program prints "x" whether compiled with -O or -O0. This does seem like a bug to me. Cheers, Kirsten -- Kirsten Chevalier* chevalier@alum.wellesley.edu *Often in error, never in doubt "Live fast, love hard, and wear corrective lenses if you need them." --Webb Wilder