This is a rant.
So I've been using CentOS at work, and a long-standing suspicion that RPM distros are built by children is being repeatedly confirmed.
Like other reasonable distributions, CentOS splits debug symbols into a packages
separate from the binary package itself, so that users don't need to always
download debug symbols they almost never use. Unlike other reasonable
distributions, CentOS creates one debug-symbol package per source, not per
binary package. So if you have a source package called foo that builds
binary packages foo, foo-devel and foo-tools then RPM distros generate a
single foo-debuginfo package for all the symbols. This in itself isn't stupid,
but it raises a question: what should foo-debuginfo depend on? After all,
debug symbols are only useful together with the binary they were generated from.
If you have a 1-1 relationship between binary packages and their debug symbol
package, then the answer is obvious: foo-tools-debuginfo should depend on
foo-tools of the exact same version. But if you have the joint debug
package, then should it depend on foo? foo-devel? foo-tools? Clearly the
answer is to depend on foo of the same version or foo-devel of the same
version or foo-tools of the same version. But since RPM was built by
children, it doesn't support this basic boolean specification.
So what do they do? They simply omit the dependency! So a hapless user installs
foo and foo-debuginfo and successfully debugs something. Then at some later
point they update foo, which does not pull in a new foo-debuginfo. THEN
they try to debug something, and stuff doesn't work. So they then spend valuable
time debugging this bullshit and write an annoyed blog post.
In my case this was slightly more complex because the package in question was python, and the debuginfo package contains not just the debug symbols, but also gdb scripts to get python-level instrumentation. So figuring out where and how gdb loads its scripts was the first step. And this is exactly why anal dependencies are important: because the world is complicated and by omitting something like this you're wasting somebody's time and defeating the whole point of having a distro.