File ‘data.table/libs/data_table.so’:
  Found non-API calls to R: ‘LEVELS’, ‘SETLENGTH’, ‘SET_GROWABLE_BIT’,
    ‘SET_TRUELENGTH’, ‘STRING_PTR’, ‘TRUELENGTH’

Compiled code should not call non-API entry points in R.

See ‘Writing portable packages’ in the ‘Writing R Extensions’ manual,
and section ‘Moving into C API compliance’ for issues with the use of
non-API entry points.
File ‘data.table/libs/data_table.so’:
  Found non-API calls to R: ‘LEVELS’, ‘SETLENGTH’, ‘SET_GROWABLE_BIT’,
    ‘SET_TRUELENGTH’, ‘STRING_PTR’, ‘TRUELENGTH’

Compiled code should not call non-API entry points in R.

See ‘Writing portable packages’ in the ‘Writing R Extensions’ manual,
and section ‘Moving into C API compliance’ for issues with the use of
non-API entry points.
File ‘data.table/libs/data_table.so’:
  Found non-API calls to R: ‘LEVELS’, ‘SETLENGTH’, ‘SET_GROWABLE_BIT’,
    ‘SET_TRUELENGTH’, ‘STRING_PTR’, ‘TRUELENGTH’

Compiled code should not call non-API entry points in R.

See ‘Writing portable packages’ in the ‘Writing R Extensions’ manual,
and section ‘Moving into C API compliance’ for issues with the use of
non-API entry points.
File ‘data.table/libs/data_table.so’:
  Found non-API calls to R: ‘LEVELS’, ‘SETLENGTH’, ‘SET_GROWABLE_BIT’,
    ‘SET_TRUELENGTH’, ‘STRING_PTR’, ‘TRUELENGTH’

Compiled code should not call non-API entry points in R.

See ‘Writing portable packages’ in the ‘Writing R Extensions’ manual,
and section ‘Moving into C API compliance’ for issues with the use of
non-API entry points.
File 'data.table/libs/x64/data_table.dll':
  Found non-API calls to R: 'LEVELS', 'SETLENGTH', 'SET_GROWABLE_BIT',
    'SET_TRUELENGTH', 'STRING_PTR', 'TRUELENGTH'

Compiled code should not call non-API entry points in R.

See 'Writing portable packages' in the 'Writing R Extensions' manual,
and section 'Moving into C API compliance' for issues with the use of
non-API entry points.
installed size is  5.6Mb
  sub-directories of 1Mb or more:
    libs   1.8Mb
installed size is  5.9Mb
  sub-directories of 1Mb or more:
    libs   2.0Mb
installed size is  5.6Mb
  sub-directories of 1Mb or more:
    libs   1.8Mb
installed size is  5.9Mb
  sub-directories of 1Mb or more:
    libs   2.0Mb