$ strace -e trace=execve ./666330.pl
execve("./666330.pl", ["./666330.pl"], [/* 24 vars */]) = 0
execve("/home/almut/bin/perl -w", ["perl -w", "./666330.pl"], [/* 24 vars */]) = -1 ENOENT (No such file or directory)
execve("/usr/local/bin/perl -w", ["perl -w", "./666330.pl"], [/* 24 vars */]) = -1 ENOENT (No such file or directory)
execve("/usr/bin/perl -w", ["perl -w", "./666330.pl"], [/* 24 vars */]) = -1 ENOENT (No such file or directory)
execve("/bin/perl -w", ["perl -w", "./666330.pl"], [/* 24 vars */]) = -1 ENOENT (No such file or directory)
execve("/usr/bin/X11/perl -w", ["perl -w", "./666330.pl"], [/* 24 vars */]) = -1 ENOENT (No such file or directory)
/usr/bin/env: perl -w: No such file or directory