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I ran the Coverity static analyzer[1] on libguestfs, and fixed many errors as a result. Coverity found some errors in gnulib, but it doesn't seem to be worth following those up since the version of gnulib we are using is so old. There are a couple more errors (possibly 1 false-positive) which I'm going to send in a separate email. BTW all the errors found by Coverity were in the daemon