fixup variables

NikolajBjorner · NikolajBjorner · commit b60e1a2ed221 · 2024-10-03T20:06:45.000-07:00
Signed-off-by: Nikolaj Bjorner &lt;nbjorner@microsoft.com&gt;
diff --git a/src/ast/rewriter/var_subst.cpp b/src/ast/rewriter/var_subst.cpp
@@ -59,7 +59,10 @@ expr_ref var_subst::operator()(expr * n, unsigned num_args, expr * const * args)
                 new_args.push_back(arg);
             else {
                 unsigned idx = to_var(arg)->get_idx();
-                new_args.push_back(m_std_order ? args[num_args - idx - 1] : args[idx]);
+                expr* new_arg = m_std_order ? args[num_args - idx - 1] : args[idx];
+                if (!new_arg)
+                    new_arg = arg;
+                new_args.push_back(new_arg);
             }
         }
         result = m.mk_app(to_app(n)->get_decl(), new_args.size(), new_args.data());

Original file line number	Diff line number	Diff line change
`@@ -59,7 +59,10 @@ expr_ref var_subst::operator()(expr * n, unsigned num_args, expr * const * args)`
`59`	`59`	`new_args.push_back(arg);`
`60`	`60`	`else {`
`61`	`61`	`unsigned idx = to_var(arg)->get_idx();`
`62`		`- new_args.push_back(m_std_order ? args[num_args - idx - 1] : args[idx]);`
	`62`	`+ expr* new_arg = m_std_order ? args[num_args - idx - 1] : args[idx];`
	`63`	`+ if (!new_arg)`
	`64`	`+ new_arg = arg;`
	`65`	`+ new_args.push_back(new_arg);`
`63`	`66`	`}`
`64`	`67`	`}`
`65`	`68`	`result = m.mk_app(to_app(n)->get_decl(), new_args.size(), new_args.data());`