I had the same problem and for me it was due to the name I had given the Xcode application.
I was still working on production code in 4.6 when the GM version of 5 came out. Prior releases had DPn appended but the GM was called "Xcode" so I renamed it to "Xcode 5". That space was my problem.
Looking in the console log and expanding [symbolicatecrash] stderr: I found the following line after it started looking for my app's symbols:
sh: /Applications/Xcode: No such file or directory
Renaming the application to "Xcode5" and hitting re-symbolicate immediately symbolicated the crash log.
That may not be your exact problem but it's certainly worth expanding that stderr: section in the console log and looking for any errors related to fetching the symbol file for your app.