fix corner case in reduce_vars (#4569)

fixes #4568
2021-01-18 22:34:48 +00:00
parent e23a10f7f9
commit b57bae4b9e
3 changed files with 49 additions and 1 deletions
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -9733,7 +9733,7 @@ merge(Compressor.prototype, {
                        single_use = false;
                    }
                    if (single_use) fixed.parent_scope = self.scope;
-                } else if (!fixed || !fixed.is_constant_expression()) {
+                } else if (!fixed || !fixed.is_constant_expression() || fixed.drop_side_effect_free(compressor)) {
                    single_use = false;
                }
            }