configure flag request

[Marc Espie]

Such machines are broken.
You may get away with it on specific occasions.
Don't count on it.

I certainly hope that things will get worse, specifically, that
gcc optimizations will get better, and the compiler will produce 
faster code.... all with a chance that your L2 cache won't catch
up if it's broken.

You're looking in the wrong place. Complain to the PC's manufacturer.