michael/lean2
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

fix(library/tactic/exact_tactic): segfault when accessing head of empty list

Browse source 
closes #485
This commit is contained in:
Leonardo de Moura 2015-03-23 18:58:15 -07:00
parent ac30052a29
commit 38a63a8a58
1 changed files with 8 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
src/library/tactic/exact_tactic.cpp
View file

@ -24,10 +24,14 @@ tactic exact_tactic(elaborate_fn const & elab, expr const & e, bool enforce_type
if (auto new_e = elaborate_with_respect_to(env, ios, elab, new_s, e, some_expr(t),
report_unassigned, enforce_type_during_elaboration)) {
goals const & gs = new_s.get_goals();
goal const & g = head(gs);
substitution subst = new_s.get_subst();
assign(subst, g, *new_e);
return some(proof_state(new_s, tail(gs), subst));
if (gs) {
goal const & g = head(gs);
substitution subst = new_s.get_subst();
assign(subst, g, *new_e);
return some(proof_state(new_s, tail(gs), subst));
} else {
return some_proof_state(new_s);
}
}
return none_proof_state();
});