Linux – Why are there no -dev packages in Arch Linux

I don't have an answer to this precise issue, but I can try to give you a hint of what may be happening: Missing dependencies in Makefiles.

Example:

target: a.bytecode b.bytecode
    link a.bytecode b.bytecode -o target

a.bytecode: a.source
    compile a.source -o a.bytecode

b.bytecode: b.source
    compile b.source a.bytecode -o a.bytecode

If you call make target everything will compile correctly. Compilation of a.source is performed (arbitrarily, but deterministically) first. Then compilation of b.source is performed.

But if you make -j2 target both compile commands will be run in parallel. And you'll actually notice that your Makefile's dependencies are broken. The second compile assumes a.bytecode is already compiled, but it does not appear in dependencies. So an error is likely to happen. The correct dependency line for b.bytecode should be:

b.bytecode: b.source a.bytecode

To come back to your problem, if you are not lucky it's possible that a command hang in a 100% CPU loop, because of a missing dependency. That's probably what is happening here, the missing dependency couldn't be revealed by a sequential build, but it has been revealed by your parallel build.

In Debian and derivatives there are six types of dependencies:

• pre-depends
• depends
• recommends
• suggests
• build-depends
• build-depends-indep

Each of these give corresponding reverse dependencies. To list them you can use grep-dctrl:

grep-dctrl -FBuild-Depends mypackage -w -sPackage /var/lib/apt/lists/*Sources

will list all the packages which build-depend on mypackage, i.e. mypackage's non-recursive reverse build-dependencies.