Re: [PATCH][Ada] arm-linux sjlj port

[Mikael Pettersson <mikpe@it.uu.se>]

Laurent GUERBY writes:
 > > Although this patch is completely in the Ada backend, and thus has very
 > > little to do with the ARM port maintenance, I'm concerned that we are
 > > trying to create an SJLJ port of GCC for ARM linux.  Why is that needed?
 > > Why aren't we using the unwind tables?
 > > 
 > > Having an SJLJ port (in addition to being very poor performance) seems
 > > the wrong way to go to me, as it will just cause confusion for our
 > > users.
 > 
 > A non-SJLJ (ZCX in Ada terminology) port would need someone writting the
 > personality routine for Ada, that is to say add some stuff in
 > gcc/ada/raise-gcc.c for arm EABI. I might get enough time in the future
 > to try to do so but I've zero experience in this area (both on the Ada
 > side and on the EH side) so even if the patch will likely end up
 > trivial it will take me a long while to figure it out.

I had a look last week at gcc's EH handling. For c++, java, and obj-c
the ARM EABI support looks pretty much the same, and while not small
(much #ifdef code) does look simple enough. The Ada EH code looks
entirely different and frankly I have absolutely no clue where or how
to modify it for ARM EABI.

So right now we have a choice of (a) no Ada for ARM EABI, or (b)
an SJLJ Ada for ARM EABI. With (b) we at least have a working and
testable system until someone can work out the ZCX EH details.

/Mikael