Index: lib/Format/Format.cpp
===================================================================
--- lib/Format/Format.cpp
+++ lib/Format/Format.cpp
@@ -1514,8 +1514,8 @@
         "UIView",
     };
 
-    auto LineContainsObjCCode = [&Keywords](const AnnotatedLine &Line) {
-      for (const FormatToken *FormatTok = Line.First; FormatTok;
+    for (auto Line : AnnotatedLines) {
+      for (const FormatToken *FormatTok = Line->First; FormatTok;
            FormatTok = FormatTok->Next) {
         if ((FormatTok->Previous && FormatTok->Previous->is(tok::at) &&
              (FormatTok->isObjCAtKeyword(tok::objc_interface) ||
@@ -1535,14 +1535,7 @@
                                TT_ObjCMethodSpecifier, TT_ObjCProperty)) {
           return true;
         }
-      }
-      return false;
-    };
-    for (auto Line : AnnotatedLines) {
-      if (LineContainsObjCCode(*Line))
-        return true;
-      for (auto ChildLine : Line->Children) {
-        if (LineContainsObjCCode(*ChildLine))
+        if (guessIsObjC(Line->Children, Keywords))
           return true;
       }
     }
Index: unittests/Format/FormatTest.cpp
===================================================================
--- unittests/Format/FormatTest.cpp
+++ unittests/Format/FormatTest.cpp
@@ -12159,6 +12159,12 @@
             guessLanguage("foo.h", "#define FOO ({ std::string s; })"));
   EXPECT_EQ(FormatStyle::LK_ObjC,
             guessLanguage("foo.h", "#define FOO ({ NSString *s; })"));
+  EXPECT_EQ(
+      FormatStyle::LK_Cpp,
+      guessLanguage("foo.h", "#define FOO ({ foo(); ({ std::string s; }) })"));
+  EXPECT_EQ(
+      FormatStyle::LK_ObjC,
+      guessLanguage("foo.h", "#define FOO ({ foo(); ({ NSString *s; }) })"));
 }
 
 } // end namespace