diff options
Diffstat (limited to 'Doc/api')
| -rw-r--r-- | Doc/api/newtypes.tex | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Doc/api/newtypes.tex b/Doc/api/newtypes.tex index 8d862db..69c49f2 100644 --- a/Doc/api/newtypes.tex +++ b/Doc/api/newtypes.tex @@ -465,6 +465,14 @@ Foo_Type.ob_type = &PyType_Type; has a non-zero \member{tp_itemsize}, it is generally not safe to set \member{tp_itemsize} to a different non-zero value in a subtype (though this depends on the implementation of the base type). + + A note about alignment: if the variable items require a particular + alignment, this should be taken care of by the value of + \member{tp_basicsize}. Example: suppose a type implements an array + of \code{double}. \member{tp_itemsize} is \code{sizeof(double)}. + It is the programmer's responsibility that \member{tp_basicsize} is + a multiple of \code{sizeof(double)} (assuming this is the alignment + requirement for \code{double}). \end{cmemberdesc} \begin{cmemberdesc}{PyTypeObject}{destructor}{tp_dealloc} |