[Bug libstdc++/123211] Consider specializing ranges::distance for join_view

"cvs-commit at gcc dot gnu.org via Gcc-bugs" <[email protected]> Fri, 31 Jul 2026 18:57:05 +0000

Newsgroups	gmane.comp.gcc.bugs
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123211

--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Patrick Palka <[email protected]>:

https://gcc.gnu.org/g:15505d012872ddb4c20916c41284e913727b4c80

commit r17-2859-g15505d012872ddb4c20916c41284e913727b4c80
Author: Patrick Palka <[email protected]>
Date:   Fri Jul 31 14:56:29 2026 -0400

    libstdc++: Optimize ranges::distance for segmented iterators [PR123211]

    For segmented iterators, ranges::distance is equivalent to the sum of
    ranges::distance of each of its segments.

            PR libstdc++/123211

    libstdc++-v3/ChangeLog:

            * include/bits/ranges_base.h (__distance_fn::operator()): For
            the non-sized-sentinel overload, recursively handle segmented
            iterators via __for_each_segment.

    Reviewed-by: Jonathan Wakely <[email protected]>