3 files changed, 22 insertions, 1 deletions
diff --git a/clang/include/clang/Lex/Token.h b/clang/include/clang/Lex/Token.h
index a048757ff35..a4b4e125575 100644
--- a/clang/include/clang/Lex/Token.h
+++ b/clang/include/clang/Lex/Token.h
@@ -23,6 +23,7 @@
 
 namespace clang {
 
+class Decl;
 class IdentifierInfo;
 
 /// Token - This structure provides full information about a lexed token.
@@ -58,6 +59,8 @@ class Token {
   ///    may be dirty (have trigraphs / escaped newlines).
   ///  Annotations (resolved type names, C++ scopes, etc): isAnnotation().
   ///    This is a pointer to sema-specific data for the annotation token.
+  ///  Eof:
+  //     This is a pointer to a Decl.
   ///  Other:
   ///    This is null.
   void *PtrData;
@@ -164,12 +167,23 @@ public:
     assert(!isAnnotation() &&
            "getIdentifierInfo() on an annotation token!");
     if (isLiteral()) return nullptr;
+    if (is(tok::eof)) return nullptr;
     return (IdentifierInfo*) PtrData;
   }
   void setIdentifierInfo(IdentifierInfo *II) {
     PtrData = (void*) II;
   }
 
+  const Decl *getDecl() const {
+    assert(is(tok::eof));
+    return reinterpret_cast<const Decl *>(PtrData);
+  }
+  void setDecl(const Decl *D) {
+    assert(is(tok::eof));
+    assert(!PtrData);
+    PtrData = const_cast<Decl *>(D);
+  }
+
   /// getRawIdentifier - For a raw identifier token (i.e., an identifier
   /// lexed in raw mode), returns a reference to the text substring in the
   /// buffer if known.
diff --git a/clang/lib/Parse/ParseCXXInlineMethods.cpp b/clang/lib/Parse/ParseCXXInlineMethods.cpp
index e1a5b8e9945..96d35bc249c 100644
--- a/clang/lib/Parse/ParseCXXInlineMethods.cpp
+++ b/clang/lib/Parse/ParseCXXInlineMethods.cpp
@@ -218,6 +218,7 @@ void Parser::ParseCXXNonStaticMemberInitializer(Decl *VarD) {
   Eof.startToken();
   Eof.setKind(tok::eof);
   Eof.setLocation(Tok.getLocation());
+  Eof.setDecl(VarD);
   Toks.push_back(Eof);
 }
 
@@ -622,7 +623,9 @@ void Parser::ParseLexedMemberInitializer(LateParsedMemberInitializer &MI) {
     while (Tok.isNot(tok::eof))
       ConsumeAnyToken();
   }
-  ConsumeAnyToken();
+  // Make sure this is *our* artificial EOF token.
+  if (Tok.getDecl() == MI.Field)
+    ConsumeAnyToken();
 }
 
 /// ConsumeAndStoreUntil - Consume and store the token at the passed token
diff --git a/clang/test/Parser/PR21872.cpp b/clang/test/Parser/PR21872.cpp
new file mode 100644
index 00000000000..ae0a13d9c1e
--- /dev/null
+++ b/clang/test/Parser/PR21872.cpp
@@ -0,0 +1,4 @@
+// RUN: not %clang_cc1 -fsyntax-only %s
+template <typename T> struct S {
+    int k = ((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((
+int f;