On Wednesday, 18 February 2015 at 13:07:12 UTC, Iain Buclaw wrote:
On 18 February 2015 at 12:34, Timo Sintonen via D.gnu
<d.gnu@puremagic.com> wrote:
On Wednesday, 18 February 2015 at 12:12:04 UTC, Iain Buclaw
wrote:
You can't throw without a GC allocation currently. I'm open
to
suggestions and patches welcome.
See here:
https://github.com/D-Programming-GDC/GDC/blob/master/libphobos/libdruntime/gcc/deh.d#L152
Iain.
I was just goimg to ask about the state of this.
I have understood that this struct carries all the necessary
info trough
unwinding and it is not freed until gc frees it.
Where is the last place this struct is used. Is it in druntime
side or in
libgcc side?
The last place it is used is on the libgcc side, or at least the
generic exception header that our language-dependent header
holds.
It may be a better solution to have a static TLS pointer that
gets
new'd upon thread start. Perhaps even make it a pre-allocated
array
so we might be able to get chained exceptions working in GDC
runtime.
Could it be possible to allocate this with malloc and free
after unwinding?
I have understood that this struct is not available any more
in catch block.
Do we need many copies of this. Could it be possible to have a
static one?
See __gdc_exception_cleanup just above _d_throw. We use
destroy(p) in
the cleanup. It could work to swap 'destroy' with 'free', and
'new'
with 'calloc'. But that still doesn't help if we are throwing
an
OutOfMemory exception. It will still fail hard, rather than
bail with
a nice backtrace.
Iain
Out Of Memory is a special case and usually a fatal case. There
was some discussions lately about this but I did not follow it.
If OutOfMemory is not working anyway then we do not loose
anything? We may get the other exceptions to work. So why not
make this until we find out some better solution?
