[Sbcl-devel] alien type on build time

[Yaroslav K. <kav...@je...>]

If I define function:

* (defun get-folder-path (CSIDL)
   (with-alien ((apath (* char) (make-alien char (1+ MAX_PATH))))
     (alien-funcall
       (extern-alien "SHGetFolderPathA"
                     (function int sb-win32::handle int sb-win32::handle
                                   sb-win32::dword (* char)))
       0 CSIDL 0 0 apath)
     (cast apath c-string)))

GET-FOLDER-PATH
* (GET-FOLDER-PATH 0)

"C:\\Documents and Settings\\Kavenchuk_Yaroslav\\Рабочий стол"

- all is work. Fine! But if I put this function in win32.lisp - I get error:

; compiling (DEFUN GET-FOLDER-PATH ...)
; file: C:\gnu\home\src\sbcl\sbcl\src\code\win32.lisp
; in: DEFUN GET-FOLDER-PATH
;     (SB!ALIEN:CAST SB!WIN32::APATH SB!ALIEN:C-STRING)
; --> SB!ALIEN-INTERNALS:%CAST SB!ALIEN-INTERNALS:NATURALIZE IF
; ==>
;   NIL
;
; caught WARNING:
;   This is not a (VALUES STRING &REST T):
;     NIL

Function without initial value for local alien variable do not take error:

(defun get-error-message (err)
   (with-alien ((amsg (* char)))
     (alien-funcall
       (extern-alien "FormatMessageA@28"
                     (function dword
                               dword dword dword dword (* (* char)) 
dword dword))
       (logior FORMAT_MESSAGE_ALLOCATE_BUFFER FORMAT_MESSAGE_FROM_SYSTEM)
       0 err 0 (addr amsg) 0 0)
     (prog1 (cast amsg c-string)
       (local-free amsg))))

Why? How it to correct? Or it only at me?

Thanks!

-- 
WBR, Yaroslav Kavenchuk.