weird ksh eval behavior

[Ralf Wildenhues]

This one is the reason for a subtle CVS Libtool testsuite failure..

With ash-0.3.8, OpenBSD 3.8 'sh' and 'ksh' PD KSH v5.2.14 99/07/13.2,
I get

$ false; eval 'foo=$?'; echo $foo
0

Is this a shell bug, or am I doing something wrong?
If bug, where should I report it?
If not, is this behavior considered "common knowledge" or should it be
mentioned in the Autoconf shell portability section?

With bash, Solaris ksh and several other shells I get 1, with Solaris sh
I get 255, because false returns 255 there.

Note that this is not the same bug as this one reported against pdksh
5.2.13:
| x pdksh 5.2.13, (reported by Mark Funkenhauser): eval "$(false)" does not
|   result in $? being set to 1 (is 0).
|   [fixed in 5.2.14: c_sh.c(c_eval): set exstat to subst_exstat before shell()]

Thanks, and sorry for the cross-post,
Ralf