> worse than native software outside the browser ...for typical portable C code the performance difference is surprisingly small though (within 20% or so). The

> worse than native software outside the browser ...for typical portable C code the performance difference is surprisingly small though (within 20% or so). The main advantage of native compilation targets is that you have more "manual optimization potential" via non-standard language extensions like builtins and intrinsics (usually at the cost of portability and compiler compatibility).