AW: AW: Undefined reference to `__sync_bool_compare_and_swap_4' for some Leon configurations with gfortran

[Jan.Sommer at dlr.de]

Ok, thanks for the clarification.
I will try to create a patch for gcc and put rtems CC for the discussion.

Best regards,

   Jan

> -----Ursprüngliche Nachricht-----
> Von: Sebastian Huber [mailto:sebastian.huber at embedded-brains.de]
> Gesendet: Montag, 27. Februar 2017 15:01
> An: Sommer, Jan; devel at rtems.org
> Betreff: Re: AW: Undefined reference to `__sync_bool_compare_and_swap_4'
> for some Leon configurations with gfortran
> 
> 
> 
> On 27/02/17 14:15, Jan.Sommer at dlr.de wrote:
> >> >-----Ursprüngliche Nachricht-----
> >> >Von: Sebastian Huber [mailto:sebastian.huber at embedded-brains.de]
> >> >Gesendet: Montag, 27. Februar 2017 13:46
> >> >An: Sommer, Jan;devel at rtems.org
> >> >Betreff: Re: Undefined reference to `__sync_bool_compare_and_swap_4'
> >> >for some Leon configurations with gfortran
> >> >
> > [...]
> >>> > >If I check the different libgfortran.a libraries of
> >>> > >sparc-rtems4.12/6.3.0 with nm I get libgfortran.a
> >>> > >           U __sync_bool_compare_and_swap_4
> >>> > >           U __sync_bool_compare_and_swap_4
> >> >
> >> >Is this reference generated by the compiler or some GCC runtime source
> code?
> >> >The atomic operations are implemented via the libatomic, so you
> >> >should only have __atomic_() references.
> >> >
> > I am not sure if I understand the question correctly.
> > I checked the mentioned elf.c-file
> > (https://gcc.gnu.org/viewcvs/gcc/branches/gcc-6-
> branch/libbacktrace/elf.c?view=markup#l960) and the call to
> __sync_bool_compare_and_swap_4 does not seem to be dependent on a
> configuration option of gcc.
> > The same is true for dwarf.c
> 
>  From my point of view this is a bug (use of legacy __sync_(),
> https://gcc.gnu.org/onlinedocs/gcc/_005f_005fsync-Builtins.html) in
> libbacktrace. It should use C11 atomic operations or the __atomic_()
> builtins:
> 
> https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
> 
> --
> Sebastian Huber, embedded brains GmbH
> 
> Address : Dornierstr. 4, D-82178 Puchheim, Germany
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> E-Mail  : sebastian.huber at embedded-brains.de
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> 
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