Boost 1.72: Powerpc compiler gives error on including unordered_map

[sbrahul]

When including unordered_map.hpp file, the powerpc compiler (gcc 4.7.2) gives an error inside the tuple_basic.hpp.
I am actually upgrading boost on the project from 1.42 to 1.72. I dont see any errors from the 1.42 version.

In file included from /boost/1_72_0/include/boost/tuple/tuple.hpp:28:0,
                 from /boost/1_72_0/include/boost/unordered/detail/implementation.hpp:31,
                 from /boost/1_72_0/include/boost/unordered/detail/map.hpp:6,
                 from /boost/1_72_0/include/boost/unordered/unordered_map.hpp:21,
                 from /boost/1_72_0/include/boost/unordered_map.hpp:17,
                 from build/ppc2/system/util/WeakReference.h:17,
                 from build/ppc2/system/util/WeakReference.c++:8:
/boost/1_72_0/include/boost/tuple/detail/tuple_basic.hpp:704:60: error: ignoring attributes on template argument 'void (boost::tuples::detail::swallow_assign::*(void (boost::tuples::detail::swallow_assign::*)()))()' [-Werror]
/boost/1_72_0/include/boost/tuple/detail/tuple_basic.hpp:836:37: error: ignoring attributes on template argument 'void (boost::tuples::detail::swallow_assign::*(void (boost::tuples::detail::swallow_assign::*)()))()' [-Werror]

[cmazakas]

Hmm, it seems like you're also using -Werror so all warnings are being translated into errors.

In the interim, are you able to remove -Werror or make an exception for this compiler warning?

I'll investigate this issue. Do you have a minimal complete example that demonstrates your issue?

[pdimov]

This seems to be an issue with Boost.Tuple and not Boost.Unordered.

[pdimov]

It concerns boost::tuple::ignore, but that's not used in Boost.Unordered. So the include chain seems to be a red herring.

I'm transferring this issue to Boost.Tuple.

[sbrahul]

The issue occurs when I pass "-mlongcall" option to gcc. Else, I dont see the error. Not sure how the longcall option is interfering with the code.