Index: lib/Lex/PPCaching.cpp
===================================================================
--- lib/Lex/PPCaching.cpp
+++ lib/Lex/PPCaching.cpp
@@ -97,13 +97,33 @@
 void Preprocessor::AnnotatePreviousCachedTokens(const Token &Tok) {
   assert(Tok.isAnnotation() && "Expected annotation token");
   assert(CachedLexPos != 0 && "Expected to have some cached tokens");
-  assert(CachedTokens[CachedLexPos-1].getLastLoc() == Tok.getAnnotationEndLoc()
-         && "The annotation should be until the most recent cached token");
+
+#ifndef NDEBUG
+  {
+    Token CachedLastTok = CachedTokens[CachedLexPos - 1];
+    SourceLocation CachedLastTokLoc = CachedLastTok.getLastLoc();
+    SourceLocation TokAnnEndLoc = Tok.getAnnotationEndLoc();
+
+    // The annotation should be until the most recent cached token. Since
+    // `Tok` length could be bigger than one (e.g. greatergreater '>>'), account
+    // for that case before checking the assertion.
+    if (CachedLastTokLoc != TokAnnEndLoc && !CachedLastTok.isAnnotation()) {
+      CachedLastTokLoc =
+          CachedLastTokLoc.getLocWithOffset(CachedLastTok.getLength());
+      unsigned TokAnnEndLocSize = Lexer::MeasureTokenLength(
+          SourceMgr.getSpellingLoc(TokAnnEndLoc), SourceMgr, LangOpts);
+      TokAnnEndLoc = TokAnnEndLoc.getLocWithOffset(TokAnnEndLocSize);
+    }
+
+    assert(CachedLastTokLoc == TokAnnEndLoc &&
+           "The annotation should be until the most recent cached token");
+  }
+#endif
 
   // Start from the end of the cached tokens list and look for the token
   // that is the beginning of the annotation token.
   for (CachedTokensTy::size_type i = CachedLexPos; i != 0; --i) {
-    CachedTokensTy::iterator AnnotBegin = CachedTokens.begin() + i-1;
+    CachedTokensTy::iterator AnnotBegin = CachedTokens.begin() + i - 1;
     if (AnnotBegin->getLocation() == Tok.getLocation()) {
       assert((BacktrackPositions.empty() || BacktrackPositions.back() < i) &&
              "The backtrack pos points inside the annotated tokens!");
Index: test/Parser/objcxx11-protocol-in-template.mm
===================================================================
--- test/Parser/objcxx11-protocol-in-template.mm
+++ test/Parser/objcxx11-protocol-in-template.mm
@@ -8,3 +8,11 @@
 
 vector<id<P>> v;
 vector<vector<id<P>>> v2;
+
+@protocol PA;
+@protocol PB;
+
+@class NSArray<ObjectType>;
+typedef int some_t;
+
+id<PA> FA(NSArray<id<PB>> *h, some_t group);