pkg_emit_error("Cannot solve problem using SAT solver:");
while (*failed) {
struct pkg_solve_variable *var = &problem->variables[*failed - 1];
struct pkg_solve_variable *var = &problem->variables[abs(*failed) - 1];
for (i = 0; i < kv_size(problem->rules); i++) {
rule = kv_A(problem->rules, i);