Cannot reintegrate into mixed revision working copy try updating first
Developers are fond of recounting their disastrous experiences branching and merging in Subversion and CVS. Then, you realize that while you’re not done with your branch yet, you need to get those trunk changes into your branch. You do this by taking all the changes in trunk that happened after revision 100 and applying them to your branch. In reality, you are already pretty screwed at this point, you just don’t realize it. You are happy with your branch; you want to commit it to trunk and let the rest of your team in on your brilliance.
So the state of the code on the branch is in good shape. You didn't describe why the conflicts you ran into occurred.Well truth is Subversion is still going strong and just released version 1.8.While Git is still faster for some things, Greg Stein, the former chair of the Apache Software Foundation, figures SVN is better than Git at lots of things.If merging a branch back into trunk (or into whichever other branch it was branched off from) use the "reintegrate" type of merge.If you stick to that there should be no spurious conflicts.