Description
'_libs.tslib': {'pyxfile': '_libs/tslib',
'pxdfiles': ['_libs/src/util'],
'depends': tseries_depends,
'sources': np_datetime_sources},
is not complete, in fact this directly depends on
(pandas) bash-3.2$ ls pandas/_libs/tslibs/*.pxd
pandas/_libs/tslibs/conversion.pxd pandas/_libs/tslibs/nattype.pxd pandas/_libs/tslibs/timedeltas.pxd
pandas/_libs/tslibs/frequencies.pxd pandas/_libs/tslibs/np_datetime.pxd pandas/_libs/tslibs/timezones.pxd
(pandas) bash-3.2$ ls pandas/_libs/tslib*.pxd
pandas/_libs/tslib.pxd
not really sure of the exact rule, but I think anything you cimport from a .pxd must be listed as a dep.
Now rebuilding from clean just works, but rebuilding from a change in one part of the structure will only sometimes work.