I can reproduce the issue with your sample repeated until it reaches 1010445 lines, and with the pattern `^(\d+?);(\d+?);(\d+?);[BCST]+\n(.*?\n)*\1`. The crash seems to be due to an excessive recursion (leading to stack overflow) inside libpcre, on which we have no control. However, your pattern is likely to do this, as you allow for any number of optional lines between two identical lines; this basically means that the regex can capture the whole file, and has to be matched against the whole file if there is no match. It's sad to ever find a program crashing, but in this case there isn't much we can do, and your regular expression is fairly dangerous per se, in term of performance and memory usage at the very least -- and most distros' libpcre are built to use recursion because it's faster (or so they say) but can lead to unavoidable crashes on extreme cases like this.
BTW, I'm not sure it's what you want, but if you choose to be ungreedy on the number of lines allowed between the start and end, it is a lot less likely to crash (`^(\d+?);(\d+?);(\d+?);[BCST]+\n(.*?\n)*?\1`) -- but it sill will if there is no match for one of the first lines. IMO, this is a case of "wontfix", both because we can't do anything about it, and it's caused by a pathological match -- which is exactly what is asked for. -- You are receiving this because you are subscribed to this thread. Reply to this email directly or view it on GitHub: https://github.com/geany/geany/issues/1586#issuecomment-417852625
