diff options
Diffstat (limited to 'generic/regc_nfa.c')
| -rw-r--r-- | generic/regc_nfa.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/generic/regc_nfa.c b/generic/regc_nfa.c index c5d7bc9..741887f 100644 --- a/generic/regc_nfa.c +++ b/generic/regc_nfa.c @@ -859,6 +859,25 @@ pull( } /* + * DGP 2007-11-15: Cloning a state with a circular constraint on its list + * of outs can lead to trouble [Bug 1810038], so get rid of them first. + */ + + for (a = from->outs; a != NULL; a = nexta) { + nexta = a->outchain; + switch (a->type) { + case '^': + case '$': + case BEHIND: + case AHEAD: + if (from == a->to) { + freearc(nfa, a); + } + break; + } + } + + /* * First, clone from state if necessary to avoid other outarcs. */ @@ -997,6 +1016,28 @@ push( } /* + * DGP 2007-11-15: Here we duplicate the same protections as appear + * in pull() above to avoid troubles with cloning a state with a + * circular constraint on its list of ins. It is not clear whether + * this is necessary, or is protecting against a "can't happen". + * Any test case that actually leads to a freearc() call here would + * be a welcome addition to the test suite. + */ + + for (a = to->ins; a != NULL; a = nexta) { + nexta = a->inchain; + switch (a->type) { + case '^': + case '$': + case BEHIND: + case AHEAD: + if (a->from == to) { + freearc(nfa, a); + } + break; + } + } + /* * First, clone to state if necessary to avoid other inarcs. */ |