Interfacing C with "function F return SYSTEM.ADDRESS;"

Interfacing C with "function F return SYSTEM.ADDRESS;"

[Pascal MALAISE]

Hi,
I'd like to interface a C function: char *f() to ada95,
using gnat on Linux.
(in fact f is "char *strerror(int errnum);" and returns a pointer to a
static string)

With gnat 3.9 I used something like
type STR_ACCESS is access STRING.
function F return STR_ACCESS;
pragama IMPORT...
It compiled and was OK

With gnat 3.10p, I get
warning: return type of "F" does not correspond to C pointer
I try:
function F return SYSTEM.ADDRESS;
then a unchecked_conversion from SYSTEM.ADDRESS to STR_ACCESS
I get
warning: types for unchecked conversion have different sizes

OK. Access to unconstrained array is not an address any more.

I think I can't use C.INTERFACE.char_array type instead of STRING for
similar reasons.

My best solution so far is to declare a local string STR and strcpy from
F result to STR'ADDRESS with
  function C_STRCPY (DEST, SRC : SYSTEM.ADDRESS) return SYSTEM.ADDRESS;
  pragma IMPORT (C, C_STRCPY, "strcpy");
then look for ASCII.NUL in STR and return the proper slice.


Any nicer (more ada like) idea?
Thank's in advance

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