[Bug c++/126310] [16/17 regression] Miscompile due to erroneous value range propagation since r16-5887

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126310

--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-16 branch has been updated by Jason Merrill
<[email protected]>:

https://gcc.gnu.org/g:2e1c4ce1640aa26f391e7aaf842500d98b9bc483

commit r16-9417-g2e1c4ce1640aa26f391e7aaf842500d98b9bc483
Author: Jason Merrill <[email protected]>
Date:   Mon Jul 27 13:25:33 2026 -0400

    c++: vrp and pmf conversion [PR126310]

    Here when trying to convert to EncodeFnTy, aka void (sub::*)(int&&), we
were
    instead converting to void (sub::*)(ValuePart&&), and the optimization
added
    by r16-5887 got confused by the values in the array initializer having
    different RECORD_TYPEs (with different FIELD_DECLs) from the type of the
    array.

    So let's correct the conversion to actually end with the requested type.

            PR c++/126310

    gcc/cp/ChangeLog:

            * call.cc (standard_conversion): Don't build a mixed METHOD_TYPE if
            it isn't needed.

    gcc/testsuite/ChangeLog:

            * g++.dg/opt/pmf2.C: New test.

    (cherry picked from commit 0e429acc24a2305c77da1229c456788e50edcae9)