I will go a bit more detailed:
Originally Posted by Mr James
- you don't need to go through the code. The USE flags are displayed by emerge or eix. Their meaning can be found in corresponding ebuild or on internet. Many ebuilds use own CFLAGS overriding your choice for purpose of better optimization. There is a useflag to prevent this behavior.
- neither emerge, nor paludis recompile EVERYTHING. They automatically recompile only what is needed to be recompiled. It is also not necessary a foreground process. Its true, that sometimes you need to call revdep to rebuild everything depending upon changed package, and you will be informed to do so. Again with Ubuntu, segfaults were not uncommon.
- the world package set is unique,as in valuable, in Gentoo. You will never get any package lost over the time, just because package manager silently decided to do so. You have very differentiated list of what you want and everything else is a dynamic dependency.
You take the high road and I'll take the low road...
why would I prefer some woman to my computer?
Originally Posted by elanthis
Seriously, it's not as bad as you make it sound. Most people who try gentoo don't get further than the installation, which can take days for a novice. But upgrading software costs CPU time, not my time. I can do it as a background job or I can do it overnight (emerge -uDN world && shutdown -h now), doesn't cost time for me.
And when I need a custom patch in some package, some inofficial git version or something, gentoo actually makes it easier to get it done in a clean and reliable way, thus saving my time.
Oh, and installation? I haven't reinstalled gentoo in years, even though every bit of hardware changed at some point. cp -a /mnt/oldroot /mnt/newroot, reconfigure & install kernel, reinstall grub, modify /etc/fstab, working system. Change use flags and some configuration files, do system upgrade overnight, done. Even my notebook started out as a clone of my workstation.
Unless you start from scratch, installing gentoo doesn't take much longer than installing ubuntu. It's just less clicking in a fancy GUI installer and more knowing what you're doing.
......And I'll get to Ireland before ye...
It doesnt do reverse dependencies though. And yes come upgrade time, I've gone through dependency hell because of this. revdep-rebuild is flawed. It's advertised as calculating reverse dependencies. But in truth it actually doesnt work right. It scans through all the linking dependencies, and figures out what applications are linked against what libraries and if it finds an application that is linked against a library that has been updated, it'll recompile the application. But sometimes the library needs to be recompiled, not the application that linked against it. This is where revdep-rebuild fails.
Originally Posted by crazycheese
EDIT: About the only thing that is fail safe is emerge -e world. Even then sometimes you have to do it twice to get all the links consistent with the versions that they are linked against.
EDIT2: Or rather sometimes the library needs to be recompiled and THEN the application needs to be recompiled against it.
Originally Posted by duby229