Man pages matching name __gnu_profile::__map2umap_stack_info in section 3cxx:

__gnu_profile::__map2umap_stack_info.3cxx.en	debian 10 / libstdc++-7-doc
__gnu_profile::__map2umap_stack_info.3cxx.en	debian 10 / libstdc++-8-doc
__gnu_profile::__map2umap_stack_info.3cxx.en	debian 11 / libstdc++-9-doc