Of course I've made fence post errors. But then on constructs that would be really awkward to do without C-style for loops.

I don't think I've ever made a fence post error on

for (my $i = 0; $i < @array; $i++) {
   ...
}
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where I would not modify @array or $i, nor use $i to look elsewhere in the array. But then, this is about the only case where I would not use a C-style for loop, but a Perl style foreach.