Fixed handling of "input foo; reg [0:0] foo;"

diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 5ab778e6698b64c16cf6fe8eb63e2f21163774a9..552fc04bcf4526302b9a9859cd79fbc165c4a6f4 100644 (file)
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -186,6 +186,13 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
                                        AstNode *first_node = this_wire_scope[node->str];
                                        if (!node->is_input && !node->is_output && node->is_reg && node->children.size() == 0)
                                                goto wires_are_compatible;
+                                       if (first_node->children.size() == 0 && node->children.size() == 1 && node->children[0]->type == AST_RANGE) {
+                                               AstNode *r = node->children[0];
+                                               if (r->range_valid && r->range_left == 0 && r->range_right == 0) {
+                                                       delete r;
+                                                       node->children.pop_back();
+                                               }
+                                       }
                                        if (first_node->children.size() != node->children.size())
                                                goto wires_are_incompatible;
                                        for (size_t j = 0; j < node->children.size(); j++) {