fix corner case in collapse_vars (#4071)

fixes #4070
2020-08-25 10:23:36 +01:00
parent 1caf7c7bd2
commit a31c27c7cf
2 changed files with 23 additions and 1 deletions
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1286,7 +1286,7 @@ merge(Compressor.prototype, {
                        col: node.start.col
                    });
                    if (candidate instanceof AST_UnaryPostfix) {
-                        lhs.definition().fixed = false;
+                        if (lhs instanceof AST_SymbolRef) lhs.definition().fixed = false;
                        return make_node(AST_UnaryPrefix, candidate, candidate);
                    }
                    if (candidate instanceof AST_VarDef) {