printf with gap in indexed conversion specifier try to fetch a number in the hole.

[phidebian]

$ echo $KSH_VERSION
Version AJM 93u+m/1.1.0-alpha+b5087279 2025-01-15

$ printf '%s %5$s\n' 1 2 3
1

$ printf '%s %5$s\n' A B C
./arch/linux.i386-64/bin/ksh: printf: B: parameter not set
./arch/linux.i386-64/bin/ksh: printf: C: parameter not set
A

This is a leftover from ancient code...

Expected result

$ printf '%s %5$s\n' 1 2 3
1

$ printf '%s %5$s\n' A B C
A

[phidebian]

Fixed with commit e322dbc

Apologies, in sftable.c I did the 1 char fix

fp[n].ft.fmt = 'd';

into

fp[n].ft.fmt = 'c';

But I forgot to update the comment
/* gap: pretend it's a 'd' pattern */

Cheers