Mirko Vukovic <mirko.vuko...@gmail.com> writes: > This message has two audiences: One the general CFFI group, and second the > GSL maintainer. > > This is using latest CCL and SBCL on 64-bit Windows 7, and MSYS2 running > 64-bit MinGW and its GSL2.0 and 2.1. > > Running GSL 2.0 and 2.1 under GSLL resulted in exception violations. I > could eliminate them by specifying the length of an integer as 8 instead of > 4 bytes. > > My question has to do with the origin of this specification, since it is > derived from CFFI and GSLL, not hard-coded. > > Specifically, in GSLL, the following code in init/types.lisp: > (case (cffi:foreign-type-size :long) > *(8 (push :int64 *features*))* > *(4 (push :int32 *features*))*) > > evaluates to 4, pushing :int32 into *features*. Here is some additional > output of cffi:foreign-type-size on my machine: > > GSL> (cffi:foreign-type-size :double) > 8 > GSL> (cffi:foreign-type-size :long) > 4 > GSL> (cffi:foreign-type-size :long-long) > 8 > GSL> (cffi:foreign-type-size :int) > 4 > > This feature eventually makes its way to other code in GSLL. In the Linear > Algebra module, the function make-permutation (in data/permutation.lisp) > has this line: > (make-instance > 'permutation > :element-type '(unsigned-byte *#+int64 64* *#+int32 32*) > :dimensions (if (typep n 'permutation) (grid:dimensions n) (list n))))) > > In my environment element type resulted in unsigned-byte 32. > > When I hard-coded my features to :int64 (and unsigned-byte 64), all the > exception errors disappeared. > > I hope this gives enough background to fix this error (either in my setup, > gsll, or cffi). long on 64-bit windows is indeed 4-byte long, so it cannot be used to determine word length.
I would suggest using (cffi:foreign-type-size :pointer) instead. I would also suggest using DEFTYPE: (deftype word () `(unsigned-byte ,(* (cffi:foreign-type-size :pointer) 8))) -- With best regards, Stas.
