drop anonymous function name when overshadowed by other declarations (#1712)

fixes #1709

1 files changed, 7 insertions, 3 deletions

diff --git a/lib/compress.js b/lib/compress.js
index e2fde883..e4863d9f 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -1850,9 +1850,13 @@ merge(Compressor.prototype, {
                 function before(node, descend, in_list) {
                     if (node instanceof AST_Function
                         && node.name
-                        && !compressor.option("keep_fnames")
-                        && !(node.name.definition().id in in_use_ids)) {
-                        node.name = null;
+                        && !compressor.option("keep_fnames")) {
+                        var def = node.name.definition();
+                        // any declarations with same name will overshadow
+                        // name of this anonymous function and can therefore
+                        // never be used anywhere
+                        if (!(def.id in in_use_ids) || def.orig.length > 1)
+                            node.name = null;
                     }
                     if (node instanceof AST_Lambda && !(node instanceof AST_Accessor)) {
                         var trim = !compressor.option("keep_fargs");