[Bug c++/56665] -O2 with -fno-strict-aliasing makes boost::spirit::classic::assign_a not working

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56665

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |trippels at gcc dot gnu.org

--- Comment #5 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Created attachment 37607
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37607&action=edit
reduced testcase

Here's a somewhat reduced testcase that fails with gcc-5 and gcc-6.
I haven't looked deeper yet.

markus@x4 tmp % clang++ -std=c++14 -O2 boost.ii && ./a.out
markus@x4 tmp % clang++ -std=c++14 -O3 boost.ii && ./a.out
markus@x4 tmp % clang++ -std=c++14 -O0 boost.ii && ./a.out
markus@x4 tmp % icpc -std=c++14 -O0 boost.ii && ./a.out
markus@x4 tmp % icpc -std=c++14 -O2 boost.ii && ./a.out
markus@x4 tmp % icpc -std=c++14 -O3 boost.ii && ./a.out
markus@x4 tmp % g++ -std=c++14 -O1 boost.ii && ./a.out
markus@x4 tmp % g++ -std=c++14 -O2 boost.ii && ./a.out
[1]    12466 abort      ./a.out