Re: Incomplete type generic formal interactions with Implicit_Dereference

[Simon Wright <simon@pushface.org>]

Jere <jhb.chat@gmail.com> writes:

> There were actually two bugs.
> One occurred on both GNAT GPL 2017 and GNAT FSF 7.2 on mingw64/msys2
> x86_64 A second one only affected GNAT FSF 7.2 on mingw64/msys2 x86_64
>
> The odd thing is for the second bug, GNAT GPL is 6.3, while the FSF is
> 7.2, yet the bug was fixed for the GPL version (6.3) and not the FSF
> version (7.2).
>
> I also wasn't sure if I should have reported the bug to FSF directly
> or to the maker of the mingw64 port of it.  Based on your reply, it
> sounds like I should report that second one to FSF directly?  Given
> that they don't seem to be incorporating bug fixes from GPL into FSF,
> I am concerned that the first bug I submitted to Adacore may not get
> fixed in the FSF version. It might, I just don't know since one of the
> bugs is fixed in an earlier version of GNAT but not a later version.

Under those circumstances I'd report the FSF bugs to FSF (I've been
tracking the GCC 8 developments so that I can leap in with macOS
binaries ASAP after the release!, so I'd check whether the bug was fixed
in 8).

AdaCore's timeline vs FSF isn't straighforward (there's some
not-up-to-date info at [1]).

AdaCore produce a Pro release about once a year, which they base on a
well-known GCC release (in the case of GNAT GPL 2017, 6.3). This
involves changes to Ada front-end code, to the C back-end code, and to
the interface between them (and of course to Ada & C in the runtime).

FSF GCC begins a new major release phase (currently for 8) also
approximately once a year, not synced with AdaCore's releases. What
AdaCore do (visibly, anyway) is to port the changes made in their own
source tree at that time to the FSF tree; there's commonly a rush of
commits at this point. After that, things slow down and bugs get fixed.

So one would expect some of the bugs still present in GCC 7 to have been
fixed in the GPL 2017 release (and, hopefully, in GCC 8).

[1] https://people.debian.org/~lbrenta/debian-ada-policy.html#Timeline-of-GNAT-releases