From e13615549ef15954fa7317a504652b82cbb93c1c Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Sat, 15 May 2021 19:12:58 +0100
Subject: [PATCH] fix corner case in `pure_getters` (#4940)

fixes #4939
---
 lib/compress.js               |  3 ++-
 test/compress/pure_getters.js | 26 ++++++++++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/lib/compress.js b/lib/compress.js
index 1c49ee79..6bc5d3b4 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -3776,7 +3776,8 @@ merge(Compressor.prototype, {
         def(AST_Null, return_true);
         def(AST_Object, function(compressor, force) {
             return is_strict(compressor, force) && !all(this.properties, function(prop) {
-                return prop instanceof AST_ObjectKeyVal;
+                if (!(prop instanceof AST_ObjectKeyVal)) return false;
+                return !(prop.key == "__proto__" && prop.value._dot_throw(compressor, force));
             });
         });
         def(AST_ObjectIdentity, function(compressor, force) {
diff --git a/test/compress/pure_getters.js b/test/compress/pure_getters.js
index 2a20c339..935b3e31 100644
--- a/test/compress/pure_getters.js
+++ b/test/compress/pure_getters.js
@@ -1638,3 +1638,29 @@ nested_property_assignments_3: {
     }
     expect_stdout: "PASS"
 }
+
+issue_4939: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        ({
+            __proto__: {
+                get p() {
+                    console.log("PASS");
+                },
+            },
+        }).p;
+    }
+    expect: {
+        ({
+            __proto__: {
+                get p() {
+                    console.log("PASS");
+                },
+            },
+        }).p;
+    }
+    expect_stdout: "PASS"
+}