On Mon, Sep 30, 2013 at 10:35:06AM -0700, Russ Allbery wrote: > Cyril Brulebois <kibi@debian.org> writes: > > Julian Taylor <jtaylor.debian@googlemail.com> (2013-09-30): > >> At minimum the packages using Werror should be test rebuilt before each > >> new upload: > >> http://codesearch.debian.net/search?q=AM_INIT_AUTOMAKE.*-Werror > >> The list is small enough that it can be done by hand / small script. > > So that they stop using Werror? Good idea. > I use -Werror for Automake for all of the packages for which I'm upstream > and have not noticed it being a serious issue, although maybe I'm missing > something? But I didn't have any trouble regenerating the files for my > various packages with Automake 1.14. > -Werror for a compiler is a bad idea for Debian packages because, unless > you do extensive portability testing, it's quite likely that there will be > warnings on some platform on which the code is not regularly tested but > which aren't serious issues. Also, each new version of the compiler comes > with a ton of new warnings, most of which are not significant. Not really speaking to the main point of this thread since it has nothing to do with automake, but: I'm gonna go on record as disagreeing with this conventional wisdom. Yes, -Werror (or even moreso, -Wall -Werror) does often turn up a lot of false positives, and can result in a fair number of build failures for the maintainer to deal with. But the compiler is also the best code reviewer you're ever likely to encounter, and while some of these warnings will be false positives, a lot of them are real bugs - and an occasional build failure is certainly better than a broken binary in the archive. Many of the hairiest upstream bugs I've had to fix lately, including for stuff running in early boot and security-sensitive code, have been bugs that would have been caught by building with -Werror. Some people have argued that -Werror should be turned on during development only, and then disabled for upload to the archive. But this is inadequate precisely because the warnings one sees and deals with locally before upload are *not* guaranteed to be representative of the problems encountered on the buildds - in part because of architecture differences, but also because of things like binNMUs that could introduce regressions due to changes in the build-dependencies or in the compiler used. (That includes not just regressions in the set of warnings output by the compiler, but actually regressions in the functionality of the resulting binary caused by compiler changes.) Now, the maintainer could decide to watch the build logs for "important" warnings instead and fix them after upload; but I don't think it's realistic that maintainers will actually do this in practice, and in any case it does nothing to help where NMUs are concerned. So while I don't currently build all of my packages with -Werror, I think it's a perfectly reasonable thing for maintainers to choose to do, just as it is to have a policy of keeping their package lintian-clean. -- Steve Langasek Give me a lever long enough and a Free OS Debian Developer to set it on, and I can move the world. Ubuntu Developer http://www.debian.org/ slangasek@ubuntu.com vorlon@debian.org
Attachment:
signature.asc
Description: Digital signature