I inquired about the combination of SDCC with the Maxim/Dallas 89C4x0 processors last spring, and got a number of conflicting answers, some of which gave me pause.
On the 8052.com site, specifically, in thread http://www.8052.com/forum/read.phtml?id=92467 I got some information indicating that there are a number of ultra-serious bugs in SDCC that ruled out doing serious work with SDCC when using these MCU's. 
Has anyone among the developers noted these problems and addressed them in any way?  In some cases, they seem pretty serious, e.g. resulting in overlapping memory usage, limited program size, improper storage allocation, etc.
Richard Erlacher