I ran into an interesting problem today. I have a custom build task that executes when building a Team project in Microsoft’s Team Foundation Server. It creates a custom build number that follows the major.minor.build.revision format commonly used for Microsoft assemblies. However, this build task had been writing the build date (YMMDD) for the build part, and it was writing the actual build number (e.g. 221) for the revision. So a complete buld number might be 2.0.61215.203, meaning that the build happened on 12/15/2006 and it was the 203rd time we built that project. Pretty cool, eh?
Well, when I tried to build it this morning (1/2/2007), I got the following error:
Properties\AssemblyInfo.cs(32,12): error CS0647: Error emitting ‘System.Reflection.AssemblyVersionAttribute’ attribute — ‘The version specified ‘2.0.70102.203′ is invalid’
After a little digging and brainstorming with another developer, we rediscovered that each part of the full build number is actually treated as an unsigned 16-bit integer. The max value for such an integer is 65534. So, of course 70102 would cause an error.
In our case, the “minor” part is not important, so we decided to push the year over to get the following: 2.7.0102.203. Once this fix was made, our builds were successful.
Cool bug, eh?