Your right, it doesnt use any test modules, but outputs TAP directly. I cant provoke the same failures on my FC4 box, but the lines of t/astress.t you need to add some printf's around are
- test 19 -> line 108 - print out the value of $p->current_line - yours is not 17
- test 20 -> line 109 - print out the value of $p->current_column - yours is not 20
- test 24 -> line 230 - print out the values of $cmpstr and $pos - yours are not equal
Of course none of this shows you the real problem, just the symptoms. You'll probably have to run the test file under the perl debugger so you can see more - though even that is made harder by the fact that there is some XS code to deal with to, which you cant trace into with the perl debugger.
Perhaps the best you can hope for is that the differences are not important, as far as the problem you are trying to solve - perhaps their white space related.
...reality must take precedence over public relations, for nature cannot be fooled. - R P Feynmann