diff --git a/lib/compress.js b/lib/compress.js
index fdb06839..32d38cef 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -977,6 +977,9 @@ merge(Compressor.prototype, {
         def(AST_Arrow, function() {
             throw def;
         });
+        def(AST_Class, function() {
+            throw def;
+        });
         function ev(node, compressor) {
             if (!compressor) throw new Error("Compressor must be passed");
 
diff --git a/test/compress/issue-1044.js b/test/compress/issue-1044.js
new file mode 100644
index 00000000..360075a4
--- /dev/null
+++ b/test/compress/issue-1044.js
@@ -0,0 +1,9 @@
+issue_1044: {
+    options = { evaluate: true, conditionals: true };
+    input: {
+        const mixed = Base ? class extends Base {} : class {}
+    }
+    expect: {
+        const mixed = Base ? class extends Base {} : class {}
+    }
+}