Re: [RFH] Uses of output.h in the front ends

[David Edelsohn <dje dot gcc at gmail dot com>]

On Mon, Jun 4, 2012 at 3:53 PM, Steven Bosscher <stevenb.gcc@gmail.com> wrote:

> What I don't understand, is whether this is still something GNAT has
> to support, or whether this code can be deprecated/removed. And I ask
> for your help because you are one of the people who worked on this
> so-many-years ago
> (http://gcc.gnu.org/ml/gcc-patches/2004-12/msg00550.html) and because
> you obviously have much better understanding of GNAT and of how this
> kind of low-level thing works in GCC than I do.
>
> If this should continue to be supported:
> For the corresponding option for G++ (-fconserve-space) the
> documentation says that the flag isn't very useful anymore because:
> "This option is no longer useful on most targets, now that support has
> been added for putting variables into BSS without making them common."
> What I don't understand, is what this means for GNAT. (Remember, I
> help build aircraft for a living, not compilers! I can barely
> distinguish .bss from .data, and don't understand at all where/how GCC
> decides to put variables in one section or another :-D) I was hoping
> maybe you know how to rewrite that piece of code such that you get
> that uninitialized variable into BSS without DECL_COMMON.
>
> Or maybe you can tell if this code is no longer needed, so I can
> prepare a patch to remove it.

Is this feature necessary for non-ELF file formats, such as AIX XCOFF?

- David