"printf -v foo bar" sets $? to 1

[Keith Thompson]

Compilation CFLAGS: -g -O2 -Wno-parentheses -Wno-format-security
uname output: Linux bomb20 5.4.0-80-generic #90-Ubuntu SMP Fri Jul 9
22:49:44 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-pc-linux-gnu

Bash Version: 5.1
Patch Level: 4
Release Status: maint

Description:
        The builtin "printf" command with the "-v" option works
        correctly, but it reports failure by setting $? to 1.

        The problem was introduced by this commit; I've confirmed
        that it doesn't occur with its immediate predecessor.

        commit a30f513fc4cd507e74de6f0d0006b289a017a0d0
        Author: Chet Ramey <chet.ramey@case.edu>
        Date:   2021-05-13 14:49:18 -0400

            more changes to handle @ and * as associative array keys


Repeat-By:
        if printf -v foo bar ; then echo OK ; else echo FAILED ; fi