if i understood correctly, the matter is different: 
$ cat t.pl
#!/usr/bin/perl
print "foo=$foo\n";
$ perl t.pl -foo=bar
foo=

[download]
and that's is expected. 
$ cat t.pl
#!/usr/bin/perl -s
print "foo=$foo\n";
$ perl -s t.pl -foo=bar
foo=bar

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and that's too, but: 
$ cat t.pl
#!/usr/bin/perl -s
print "foo=$foo\n";
$ perl t.pl -foo=bar
foo=1

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if i call it without -s, but the shebang say -s, perl assign 1 which is neither bar or undef

Oha

update: with the help of dada i think we have figured out it was a bug in perl.c function init_argv_symbols. checking on dev.perl.org on latest 5.x sources seems fixed btw. could anyone confirm? it's long since i read C code...

In reply to Re^2: unexpected results using -s switch by oha
in thread unexpected results using -s switch by mojodaddy

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