Description
I just cleared out ~75GB of data from my temp folder, in the form of files named "stderr.txt" inside a large number of folders with names like "console27501978494037653.tmp"
In one case, a single stderr.txt file was over 18GB in size!
These files, presumably meant to be temporary, are never deleted, and can apparently grow to obscene size. Unfortunately, I did not retain any of the pathological files, nor did I attempt to view them, so I can't provide any information on what was in them (I was focused on getting my computer working again after running out of disk space on my system drive due to these files, and only later figured out that they were related to Arduino).
The large files appeared to be generated at random over the course of the past year, including both before and after I updated to Arduino 1.6.x. There were dozens of folders, but in most of the folders, the files were small; it was a few seemingly randomly distributed ones that were absolutely massive. Presumably these are created more frequently than I see them, and most of them are removed.