static assert failing while using boost bimap

[sloriot]

I recently got the following assertion in our testsuite (several versions of gcc recent and older):

**/usr/local/include/boost/multi_index/detail/node_type.hpp:41:3: error: static assertion failed: detail::is_index_list<IndexSpecifierList>::value
   41 |   BOOST_STATIC_ASSERT(detail::is_index_list<IndexSpecifierList>::value);
**

The file was recently modified in 890f0329390fac7ef7b9607f5c9dd1ef51a6779b so I was wondering it you already saw this error?

In the meantime I'll try to prepare a self-contained example.

[sloriot]

Actually the following example from the distrib produces the error:
https://www.boost.org/doc/libs/latest/libs/bimap/example/standard_map_comparison.cpp

[joaquintides]

Hi Sebastien, what version of Boost are you using? Commit boostorg/multi_index@890f032 has not been shipped yet (will be in Boost 1.91, spring 2026), and the example mentioned seems to be working ok with Boost 1.89:

https://godbolt.org/z/EoKWq93nc

[sloriot]

Hi Joaquín, the testsuite with the issue is using the HEAD of all boost packages.

[joaquintides]

Understood. So, yes, this problem stems from the breaking change in MultiIndex you mention. Working right now in

https://github.com/boostorg/bimap/tree/fix/compatibility-multi_index-1.91

[sloriot]

Thanks!