Index: clang/lib/Format/TokenAnnotator.cpp
===================================================================
--- clang/lib/Format/TokenAnnotator.cpp
+++ clang/lib/Format/TokenAnnotator.cpp
@@ -1387,7 +1387,9 @@
                Style.Language == FormatStyle::LK_Java) {
       Current.Type = TT_LambdaArrow;
     } else if (Current.is(tok::arrow) && AutoFound && Line.MustBeDeclaration &&
-               Current.NestingLevel == 0) {
+               Current.NestingLevel == 0 &&
+               !Current.Previous->is(tok::kw_operator)) {
+      // not auto operator->() -> xxx;
       Current.Type = TT_TrailingReturnArrow;
       TrailingReturnFound = true;
     } else if (Current.is(tok::star) ||
Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -4830,6 +4830,10 @@
 
 TEST_F(FormatTest, TrailingReturnType) {
   verifyFormat("auto foo() -> int;\n");
+  // correct trailing return type spacing
+  verifyFormat("auto operator->() -> int;\n");
+  verifyFormat("auto operator++(int) -> int;\n");
+
   verifyFormat("struct S {\n"
                "  auto bar() const -> int;\n"
                "};");