Re: GNAT doing macro-expansion? (Pre/Post conditions)

[Anh Vo <anhvofrcaus@gmail.com>]

On Wednesday, October 24, 2012 10:20:36 AM UTC-7, Hibou57 (Yannick Duchêne) wrote:
> Le Wed, 24 Oct 2012 18:45:27 +0200, Yannick Duchêne (Hibou57) <yannick_duchene@yahoo.fr> a écrit: > Le Wed, 24 Oct 2012 18:40:58 +0200, Yannick Duchêne (Hibou57) > <yannick_duchene@yahoo.fr> a écrit: > >> same snippet. Obviously, this does not stand for the reliable > Read “does not stand for the real thing”. > >> type A_Type is mod 256; > > Sorry, forget to say about a second variation: replace the above with > `type A_Type is new Positive;` and there will be no more error at > runtime (the first error, that is, with the useless package body still > there). That one is a lot weird. > More on that particular point. I you change `mod 256` into anything the modulo is above 256, not necessarily a power of two, as this works with `mod 257` two, then the bug disappears. The bug is there for any value below and included, 256. I suspected the element size, and indeed, that's not really the modulo, but the size. Replace `type A_Type is mod 256;` with this, with an added representation clause: type A_Type is mod 256; for A_Type'Size use 16; The module is still 256, but now the size changed, and the bug is not exposed.>>


You should file bug report for these problems. So far, I have filed two bug reports at report@gnat.com when using GNAT-GPL-2012 to compile Ada 2012 codes.