use happens at compile time, so any code in external modules actually runs in syntax check mode.

Taint mode "behaves", as you can easily find out yourself 

$ perl -Tce 'BEGIN { system <> }'
echo foo
Insecure $ENV{PATH} while running with -T switch at -e line 1, <> line
+ 1.
BEGIN failed--compilation aborted at -e line 1, <> line 1.

[download]

perl -c script.pl is not safer than running perl script.pl if script.pl is malicious. Just the chances of accidental "bad" code are smaller.

(Update: a few wording improvements)

Second update: constant folding also happens at compile time, but that's hardly unsafe.

In reply to Re: What restrictions are there on code execution when running perl in syntax check mode? by moritz
in thread What restrictions are there on code execution when running perl in syntax check mode? by ELISHEVA

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