Am 21.12.2024 um 20:21 schrieb tlaro...@kergis.com: > Problem found: NetBSD's flex doesn't understand the idiom but is used, > while (pkgsrc) flex-2.6.4 is able to interpret such regex. > > Nonetheless, has someone information about the handling of negative > chars in a regex (there are discussions, here and there, about > problems caused by a character as '-1' mistaken for EOF, so it seems > that the regex should always use unsigned char. But I guess a majority > of the code uses char, and only the ASCII range (whether these values > represent ASCII chars or not) i.e. positive values are safe.
The flex message "negative range in character class" means that in a character range [F-L], F is greater than L. It's not about negative character numbers but about a backwards range. I tried to reproduce the problem by running external/bsd/flex/bin/lex from the netbsd-8 branch, compiled on NetBSD 10.99.x, on https://raw.githubusercontent.com/wine-mirror/wine/wine-5.0.5/dlls/msxml3/xslpattern.l, but everything went fine. If you have the NetBSD 8 source at hand, you could add a printf statement right above the "negative range" message in external/bsd/flex/dist/src/parse.y: > if ($2 > $4) fprintf(stderr, "from %d to %d\n", $2, $4); Then, rebuild flex and run it on the file. I'm curious whether you can reproduce the message, and what the actual character numbers are that are backwards. Roland
