From: Juho S. <js...@ik...> - 2008-08-26 16:53:08
|
Daniel Herring <dhe...@te...> writes: > Moved; new readers please find my first message on sbcl-devel. For now, > the only confirmed bug is my confusion; the optimizer is doing something I > don't understand. > > To rephrase the original questions, > - is the FSET::LENGTH "optimization" really needed for SBCL? Only you can decide whether it's really needed. The observation that SBCL will not optimize CL:LENGTH for a type that's either nil or a vector is true. > - what's causing this warning? SBCL thinks NKEYS can be 0, which would be an invalid input value to RANDOM. > - why does it go away with the optimize debug? Because that disables enough optimizations to make sbcl no longer think there's a reasonable chance of LENGTH returning 0. -- Juho Snellman |