]] Helmut Grohne > Hi Tollef, > > On Fri, Oct 24, 2014 at 02:27:16PM +0200, Tollef Fog Heen wrote: > > Have the links created by triggers on /usr/bin/$arch-gcc. > > I have long pondered this possibility and concluded that triggers are > the wrong tool for the job. Here are a couple of reasons: > > 1. Triggering on /usr/bin/$arch-gcc is equivalent to triggering on > /usr/bin, because triggers cannot contain wildcards. Triggering on > /usr/bin is equivalent to triggering on every other package > installation. This sounds like a very bad idea.
The list of arches is effectively static (and can be gotten from dpkg), so I don't see why that matters. You'd just add a trigger on all of them. > 2. So maybe triggering on something else is better. Possibly > /usr/lib/gcc? Unfortunately, cross compilers use /usr/lib/cross-gcc, > so we'd miss them. Furthermore, it has already been pointed out that > gcc is not the only compiler and pkg-config is used for other > languages than C. Packages such as pm-utils or x11-xkb-utils work > without one. So ideally, pkg-config should trigger on the > installation of any foreign-arch package. That doesn't matter, you still need build-essential installed, which pulls in gcc. > 3. During the freeze of jessie we have seen that when triggers are done > wrong (i.e. missing noawait when it is required) causes great pain. Fair point. > So I talked to Guillem Jover and he came up with an entirely different > solution: dpkg hooks. By passing --pre-invoke or --post-invoke to dpkg, > it invokes a shell command before or after certain operations. Since > dpkg version 1.17.19, there are DPKG_HOOK_ACTION values > "add-architecture" and "remove-architecture" which trigger on dpkg > --add-architecture and dpkg --remove-architecture, i.e. exactly what we > need. > > Of course, care must be taken to not break the system with a bad hook. Interesting approach. > +post-invoke=if test \( "$DPKG_HOOK_ACTION" = add-architecture -o > "$DPKG_HOOK_ACTION" = remove-architecture \) -a -x > /usr/share/pkg-config-dpkghook; then /usr/share/pkg-config-dpkghook update; fi That runs in shell context and -o / -a are XSIsms, so should probably rather use && and || instead. > So what do you think about this approach? Can you apply it? Please Cc me > in your reply. >From a quick skim, it looks pretty good. I'll certainly play with this and assuming I don't encounter problems or concerns, merge it. Thanks, :-) -- Tollef Fog Heen UNIX is user friendly, it's just picky about who its friends are -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
