When building libgee from the dist tarball, building twice in a row fails due to a missing utils/geeutils.vapi.
Steps to reproduce:

1/ Download tarball from [1]
2/ Run ./configure && make && make clean && make

This will result in

make[2]: Entering directory '/tmp/libgee-0.18.0/gee'
/usr/bin/valac --target-glib=2.36 --hide-internal  -H gee.h --vapi gee-0.8.vapi -h gee-internals.h --internal-vapi gee-internals-0.8.vapi --library gee-0.8 --gir Gee-0.8.gir --pkg gio-2.0 --vapidir ../utils --pkg geeutils  --target-glib=2.36 --hide-internal  -C assemblyinfo.vala abstractbidirlist.vala abstractbidirsortedset.vala abstractbidirsortedmap.vala abstractcollection.vala abstractlist.vala abstractmap.vala abstractmultimap.vala abstractmultiset.vala abstractqueue.vala abstractset.vala abstractsortedmap.vala abstractsortedset.vala arraylist.vala arrayqueue.vala bidiriterator.vala bidirlist.vala bidirlistiterator.vala bidirmapiterator.vala bidirsortedset.vala bidirsortedmap.vala collection.vala comparable.vala concurrentlist.vala concurrentset.vala deque.vala functions.vala future.vala hashable.vala hashmap.vala hashmultimap.vala hashmultiset.vala hashset.vala hazardpointer.vala iterable.vala iterator.vala lazy.vala linkedlist.vala lightmapfuture.vala list.vala listiterator.vala map.vala mapiterator.vala multimap.vala multiset.vala priorityqueue.vala promise.vala queue.vala readonlybidirlist.vala readonlybidirsortedset.vala readonlybidirsortedmap.vala readonlycollection.vala readonlylist.vala readonlymap.vala readonlymultimap.vala readonlymultiset.vala readonlyset.vala readonlysortedmap.vala readonlysortedset.vala set.vala sortedmap.vala sortedset.vala streamiterator.vala task.vala teeiterator.vala timsort.vala traversable.vala treemap.vala treemultimap.vala treemultiset.vala treeset.vala unfolditerator.vala unrolledlinkedlist.vala 
error: Package `geeutils' not found in specified Vala API directories or GObject-Introspection GIR directories
Compilation failed: 1 error(s), 0 warning(s)
Makefile:1605: recipe for target 'libgee_0_8_la_vala.stamp' failed


The problem is, that utils/geeutils.vapi is not shipped in the dist tarball, but it's required to (re)build the .c files.

utils/geeutils.vapi should probably be added to EXTRA_DIST.

[1] ftp://ftp.gnome.org/pub/gnome/sources/libgee/0.18/