backend_sources += files(
'spgdoinsert.c',
'spginsert.c',
'spgkdtreeproc.c',
'spgproc.c',
'spgquadtreeproc.c',
'spgscan.c',
'spgtextproc.c',
'spgutils.c',
'spgvacuum.c',
'spgvalidate.c',
'spgxlog.c',
)