I _suspect_ this caused issues with make failing in dependency tracking
for me, like:

make[2]: Entering directory
'/home/slink/Devel/varnish-git/libvdp-pesi/src'
  CC       vdp_pesi.lo
mv: cannot stat '.deps/vdp_pesi.Tpo': No such file or directory
Makefile:700: recipe for target 'vdp_pesi.lo' failed
make[2]: *** [vdp_pesi.lo] Error 1