Hrmm ... 5.8.4/Solaris doesn't seem to do the right thing.
BEGIN {
&Internals::SvREADONLY(\undef, 0);
undef = 42;
&Internals::SvREADONLY(\undef, 1);
}
my $x = undef;
print( ((undef) ? 'True' : 'False'), $/);
print( ((defined undef) ? 'True' : 'False'), $/);
print( (($x) ? 'True' : 'False'), $/);
print( ((defined $x) ? 'True' : 'False'), $/);
--------------
True
True
False
False
Maybe the code isn't actually affecting SV_UNDEF as you think ...
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Being unknowing, is not the same as being stupid.
Expressing a contrary opinion, whether to the individual or the group, is more often a sign of deeper thought than of cantankerous belligerence.
Do not mistake your goals as the only goals; your opinion as the only opinion; your confidence as correctness. Saying you know better is not the same as explaining you know better.