Although, check out aap (http://www.a-a-p.org or http://freshmeat.net/projects/a-a-p) It's basically make with some default steps builtin that you can easily override, the power of python for any complex steps, and it does checksumming rather than just timestamp checks. It's a very cool program, I highly recommend looking at it.
To be specific, I don't think that safe and fast are mutually exclusive. Make can be made safe, used properly, there isn't anything unsafe about it, if not and you don't have your clock set or you don't have depends properly defined, then yeah, things might not build or it's possible for non-build to not error out. I know of no build system that enforces "safty" though, if you choose not to build a safe system then it's not safe. I also assert that if you're spending a lot of time solving scaling problems with make then you probably need to split your project up, it sounds like bad engineering to me; why don't you have a simple high level make that builds the components and then a make for each component? I think it's a managable problem. It's also somewhat weak to not suggest something better.
I'm just a fan, not a developer on Open64
I created the freshmeat.net entry...