[Bug libstdc++/67843] experimental/filesystem/iterators/directory_iterator.cc fails on armv5t

[hp at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67843

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |hp at gcc dot gnu.org

--- Comment #9 from Hans-Peter Nilsson <hp at gcc dot gnu.org> ---
(I finally found it - I must have written down the wrong number at the BoF!)

A sidenote: this is the "main" PR behind the ARM-libcstdc++-atomics BoF at the
recent GNU Tools Cauldron in Manchester:
<https://gcc.gnu.org/wiki/cauldron2018#Consistent_use_of_atomics_in_libstdc.2B-.2B-_across_ARM_targets>,
where IIRC there was consensus.  I don't see it communicated neither on the
lists nor here, so I'll give it a try:

As I recall it, the level of atomics support affecting the ABI is to be fixed
to the lowest denominator reached with the default configuration, and gcc will
be changed to emit the builtin preprocessor atomicity macros to match.  This
would be the new default, overridable by configure-options to the effect of the
current behavior (and maybe compile-time gcc-options as well).  A broken
combination will yield (link-time) warnings. 

This requires gcc as well as top-level configure changes.