Simon Marlow wrote:
This is part of a larger question, namely whether we can get substantial benefit for doing a tiny bit of extra work in -O0. With -O0 we're optimising for compile time in preference to code speed, although we do want to find a good compromise that doesn't generate abysmal code.
there's the other use of -O0, namely, debugging the compiler -- but then, debugging the optimizations probably requires pretty specific knowledge of what you're looking for, anyway, and testing on multiple platforms usually finds out whether a problem is with a port or with the compilation process. oh, and also that profiling/debugging optimized code can be confusing, so it might be good to avoid optimizations that have too much of that effect -Isaac