[Bug libstdc++/92546] [10/11 Regression] Large increase in preprocessed file sizes in C++2a mode

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92546

--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Jonathan Wakely
<redi@gcc.gnu.org>:

https://gcc.gnu.org/g:cbbc28706164873d0323d1a6c7988be3f4d971c9

commit r10-9057-gcbbc28706164873d0323d1a6c7988be3f4d971c9
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Nov 20 11:30:33 2020 +0000

    libstdc++: Remove <memory_resource> dependency from <regex> [PR 92546]

    Unlike the other headers that declare alias templates in namespace pmr,
    <regex> includes <memory_resource>. That was done because the
    pmr::string::const_iterator typedef requires pmr::string to be complete,
    which requires pmr::polymorphic_allocator<char> to be complete.

    By using __normal_iterator<const char*, pmr::string> instead of the
    const_iterator typedef we can avoid the completeness requirement.

    This makes <regex> smaller, by not requiring <memory_resource> and its
    <shared_mutex> dependency, which depends on <chrono>.  Backporting this
    will also help with PR 97876, where <stop_token> ends up being needed by
    <regex> via <memory_resource>.

    libstdc++-v3/ChangeLog:

            PR libstdc++/92546
            * include/std/regex (pmr::smatch, pmr::wsmatch): Declare using
            underlying __normal_iterator type, not nested typedef
            basic_string::const_iterator.

    (cherry picked from commit 640ebeb336050887cb57417b7568279c588088f0)