On Tue, Feb 21, 2017 at 5:59 AM, Stuart Henderson <s...@spacehopper.org> wrote: > I ran across this in an i386 bulk build, but it's easy to reproduce. > ocamlyacc segfaults when processing the parser from ocaml-menhir-20170101:
Pretty nice detective work -- I'd never seen this segfault before. I checked with the previous version of ocaml-menhir that was in the tree (20160303) and it has the same behaviour. So the recent update doesn't look like it introduced a regression. > > $ cd /usr/ports/devel/ocaml-menhir; make > [..] > $ cd `make show=WRKSRC`/src/_stage1 > $ for i in `jot 200`; do ocamlyacc parser.mly || echo $i; done > Segmentation fault (core dumped) > 39 > Segmentation fault (core dumped) > 49 > Segmentation fault (core dumped) > 172 > Segmentation fault (core dumped) > 180 > > Output files are zero bytes, backtrace looks like this: > > Program terminated with signal SIGSEGV, Segmentation fault. > #0 set_first_derives () at closure.c:109 > 109 cword = *vrow++; > (gdb) bt full > #0 set_first_derives () at closure.c:109 > rrow = 0x199365ec1374 > vrow = 0x1992f74b2000 > j = 62 > mask = 0 > cword = 2164277248 > rp = 0x20 > rule = -1 > i = 62 > rulesetsize = <optimized out> > varsetsize = 1 > #1 0x00001990ce60372f in generate_states () at lr0.c:155 > No locals. > #2 0x00001990ce604215 in main (argc=2, argv=0x7f7ffffd69f8) at main.c:456 > No locals. > > I know very little about OCaml so if someone's interested, could you take > a look and/or report upstream please? > I guess avsm@ might good to talk to. I've cc'd him on this thread. I also bcc'd Francois Pottier (ocaml menhir upstream) in case he has any interest in this thread. p.s. I did a local update of ocaml from 4.03.0 to 4.04.0 to see if anything's changed, but unfortunately doesn't seem to change much (at least on my end).