Every time I build in XCode 4.5 I note this step takes over a minute, in a full rebuild this step is probably as long as everything else in total!
I previously used XCode 3.2.6 and building in 4.5 is far slower. Is there anything I can do to improve this? Is there any information on what a dSYM does, I don’t recall ever seeing it on 3.2.6.
a dSYM file is used to resymbolicate your crash reports from users. Check out this Apple Tech Note, specifically the “Analyzing Crash Reports” section).
To speed things up, you could always turn off dSYM generation for your DEBUG builds and then turn it on for ADHOC and/or Store builds. Here is a related question that talks a bit about that.