The test in question is this:

is(("acdbcdbe" ~~ rx:P5/a(?:b|c|d){6,7}?(.)/ && $0), "e", 're_tests 617/1 
(801)');

It turns out that the problem is not related to P5, but happens with P6Regex as 
well:

<bartolin>  r: say ("ddd" ~~ / [ x | d ] **? 3 /)
<camelia>   rakudo-jvm fb4f16: OUTPUT«「d」␤»
<camelia>   ..rakudo-moar 637241: OUTPUT«「ddd」␤»

<bartolin>  r: say ("ddd" ~~ / [ x | d ] **? 2..3 /)
<camelia>   rakudo-jvm fb4f16: OUTPUT«「d」␤»
<camelia>   ..rakudo-moar 637241: OUTPUT«「dd」␤»

The greedy version works as expected:

<bartolin> r: say ("ddd" ~~ / [ x | d ] ** 2..3 /)
<camelia> rakudo-moar 637241, rakudo-jvm fb4f16: OUTPUT«「ddd」␤»

I was unable to golf it further, so the alternation seems to be needed to 
produce the bug.

Reply via email to