Re: MicroBlaze symver attribute support

[Michael Eager <eager@eagercon.com>]

On 2/20/23 06:54, Joel Sherrill wrote:
> 
> 
> On Mon, Feb 20, 2023 at 7:56 AM Vincent Fazio via Gcc <gcc@gcc.gnu.org 
> <mailto:gcc@gcc.gnu.org>> wrote:
> 
>     Michael, all,
> 
>     Regarding:
>     https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101766
>     <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101766>
>     https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102110
>     <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102110>
> 
>     If I understand correctly, since the GCC MicroBlaze targets generate ELF
>     images, it would seem there's no technical reason why `__attribute__
>     ((symver ...))` cannot be supported?
> 
>     The issue seems to be that the MicroBlaze targets in config.gcc do not
>     include elfos.h
>     https://github.com/gcc-mirror/gcc/blob/master/gcc/config.gcc#L2369
>     <https://github.com/gcc-mirror/gcc/blob/master/gcc/config.gcc#L2369>
> 
>     Which defines `ASM_OUTPUT_SYMVER_DIRECTIVE`
>     https://github.com/gcc-mirror/gcc/blob/master/gcc/config/elfos.h#L259 <https://github.com/gcc-mirror/gcc/blob/master/gcc/config/elfos.h#L259>
> 
>     Which is necessary for
>     https://github.com/gcc-mirror/gcc/blob/master/gcc/varasm.cc#L6260
>     <https://github.com/gcc-mirror/gcc/blob/master/gcc/varasm.cc#L6260>
> 
>     Changing the targets to include elfos.h leads to a number of
>     conflicts with
>     the target specific header (config/microblaze/microblaze.h).
> 
>     Should `ASM_OUTPUT_SYMVER_DIRECTIVE` be copied into
>     config/microblaze/microblaze.h or should the MicroBlaze targets and
>     header
>     be reworked to support elfos.h?
> 
> 
> IMO reworked to include elfos.h. During the RTEMS port, we noticed that
> some quirks on the microblaze gcc because it isn't using elfos.h. This 
> likely
> will mean it will be updated as a side-effect of normal GCC maintenance
> instead of being an odd singleton which doesn't share.
> 
> 
>     I'm asking because I've seen a number of projects run into this
>     issue (xz,
>     elfutils, libfuse, libkcapi, cryptsetup).
> 
> 
> And RTEMS.
> 
> --joel


Joel -- do you have a patch to add elfos.h to MicroBlaze?

-- 
Michael Eager