fix corner case in collapse_vars (#4892)

fixes #4891
2021-05-01 20:57:17 +01:00
parent 53b57ee57e
commit 6ab26eef6c
2 changed files with 37 additions and 1 deletions
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1884,9 +1884,17 @@ merge(Compressor.prototype, {
                    && node.name == def.name) {
                    if (!--replaced) abort = true;
                    if (is_lhs(node, multi_replacer.parent())) return node;
-                    def.replaced++;
                    var ref = rvalue.clone();
                    value_def.references.push(ref);
+                    if (abort && candidate instanceof AST_Assign
+                        && def.references.length - def.replaced - (assignments[def.name] || 0) > 1) {
+                        return make_node(AST_Assign, candidate, {
+                            operator: "=",
+                            left: node,
+                            right: ref,
+                        });
+                    }
+                    def.replaced++;
                    return ref;
                }
                // Skip (non-executed) functions and (leading) default case in switch statements