[nhc-bugs] problems installing nhc98-1.04 on cygwin

[C.Reinke]

> |   In other words, adding -lncurses as *the very first flag* in a
> |   call to gcc ain't going to help anyone. In src/tracer/hat/Makefile:
> |       LINKFLAGS= -lncurses -g
> 
> Yes, I guess this looks a little strange - but it works here.  Are you
> saying it doesn't work in Cygwin?  Nevertheless, you are right, we ought
> to change it.

The fragment of man-page I was quoting (search archives as they occur,
for currently outstanding references only) actually stems from our gcc
on Solaris installation, but it looks the same for the gcc on cygwin
version, and for the Solaris ld version, and I assume it would be
standard behaviour.

To answer your question, cygwin's gcc failed on the linking operation
in question when lncurses was given at the start, and succeeded when it
was given at the end.  Perhaps (some) Linuxes support a more convenient
behaviour for simple cases? That would be a nice trap for portable
development..

> We do not support any operation called addFinalizer.  However, we
> do have
> 
>      FFI.newForeignObj  :: FFI.Addr -> IO () -> IO FFI.ForeignObj
> 
> Is this sufficient for your purposes?

Unfortunately not. The idea, as mentioned briefly in our meeting, a few
weeks ago, was to use the (older?) addFinalizer as a hook into the
memory management, enabling GHood to show when parts of an observed
data structure get garbage collected.

Hugs and GHC support (supported?) such an operation, built around weak
pointers, but both implement optimisations that tend to move data
around, causing finalizers for anything but foreign addresses to be run
at completely unsuitable moments. I had already given up on this idea,
but Colin suggested that I might have more luck with nhc, as you have
to be more careful with such things, to support some of your profiling
tools.

Well, it was not meant to be, and accepting finalizers only for those
objects for which they will actually be run at the "right" moment is
probably the more honest approach. Would have been nice and really
useful, though..

Regards,
Claus