GCC 4.0's due out relatively soon. Think there'll be a whole bunch of early-adopters? Heh.

"For example, the current version of GCC can optimize small, local parts of a program. But one new optimization, called scalar replacement and aggregates, lets GCC find data structures that span a larger amount of source code. GCC then can break those objects apart so that object components can be stored directly in fast on-chip memory rather than in sluggish main memory."