Tricky DMD bug, but I have no idea how to report

[H. S. Teoh]

On Fri, Feb 08, 2019 at 09:42:11PM +0000, JN via Digitalmars-d-learn wrote:
> On Friday, 8 February 2019 at 21:35:34 UTC, H. S. Teoh wrote:
> > On Fri, Feb 08, 2019 at 09:23:40PM +0000, JN via Digitalmars-d-learn
> > wrote: [...]
> > > I managed to greatly reduce the source code. I have filed a bug
> > > with the reduced testcase
> > > https://issues.dlang.org/show_bug.cgi?id=19662 .
> > 
> > Haha, you were right!  It's a compiler bug, another one of those
> > nasty -O -inline bugs.  Probably a backend codegen bug.  Ran into
> > one of those before; was pretty nasty.  Fortunately it got fixed
> > soon(ish) after I made noise about it in the forum. :-P
[...]
> Luckily it's not a blocker for me, because it doesn't trigger on debug
> builds, and for release builds I can always use LDC, but still it's
> bugging me (pun intended).

Pity I still can't reproduce the problem locally. Otherwise I would
reduce it even more -- e.g., eliminate std.stdio dependency and have the
program fail on assert(obj != null), and a bunch of other things to make
it easier for compiler devs to analyze -- and perhaps look at the
generated assembly to see what went wrong.  If you have the time (and
patience) to do that, it would greatly increase the chances of this
being fixed in a timely way, since it would narrow down the bug even
more so that it's easier to find in the dmd source code.


T

-- 
I see that you JS got Bach.