Mirko Vukovic <mirko.vukovic@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.