On Mon, Jan 18, 2010 at 10:53:31AM +0100, Jim Meyering wrote: > Here's another example of appropriate use of assert. > The while loop removed below is currently guaranteed never > to be executed, since "list" is always NULL at that point. > However, you can argue that simply removing the loop is a little > risky: what if someone changes things to "goto cleanup" before > "list" reaches the final NULL? That's why I added the assertion: > to catch the potential (albeit unlikely) future coding error. I don't really consider that a net win. If we leave the current code in there and someone adds a 'goto cleanup' in future enhancement, then everything will work as design. If we replace the current code with an assert, then it will abort(), or silently do nothing & thus leak if compiled with -DNDEBUG. So while this is technically dead code at this time I don't think we should be removing it from the cleanup: block. The cleanup: blocks should be pessimistic about considering what has been cleaned up already, even if this results in possible dead code warnings. We've had many actual bugs from cleanup: blocks not free'ing stuff they should have done, many of those introduced after refactorings of original code. I realize this means that some automated code checkers like Coverity will always complain about certain things, but these are not actual bugs. Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :| -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list