Index: clang/include/clang/Basic/Attr.td
===================================================================
--- clang/include/clang/Basic/Attr.td
+++ clang/include/clang/Basic/Attr.td
@@ -1178,8 +1178,10 @@
   let SimpleHandler = 1;
 }
 
-def OpenCLUnrollHint : InheritableAttr {
+def OpenCLUnrollHint : StmtAttr {
   let Spellings = [GNU<"opencl_unroll_hint">];
+//  let Subjects = SubjectList<[ForStmt, CXXForRangeStmt, WhileStmt, DoStmt],
+//                             ErrorDiag, "'for', 'while', and 'do' statements">;
   let Args = [UnsignedArgument<"UnrollHint">];
   let Documentation = [OpenCLUnrollHintDocs];
 }
Index: clang/include/clang/Basic/DiagnosticParseKinds.td
===================================================================
--- clang/include/clang/Basic/DiagnosticParseKinds.td
+++ clang/include/clang/Basic/DiagnosticParseKinds.td
@@ -1220,9 +1220,6 @@
   "omit the namespace to add attributes to the most-recently"
   " pushed attribute group">;
 
-def err_opencl_unroll_hint_on_non_loop : Error<
-  "OpenCL only supports 'opencl_unroll_hint' attribute on for, while, and do statements">;
-
 // OpenCL EXTENSION pragma (OpenCL 1.1 [9.1])
 def warn_pragma_expected_colon : Warning<
   "missing ':' after %0 - ignoring">, InGroup<IgnoredPragmas>;
Index: clang/include/clang/Parse/Parser.h
===================================================================
--- clang/include/clang/Parse/Parser.h
+++ clang/include/clang/Parse/Parser.h
@@ -2818,17 +2818,6 @@
   void ParseBorlandTypeAttributes(ParsedAttributes &attrs);
   void ParseOpenCLKernelAttributes(ParsedAttributes &attrs);
   void ParseOpenCLQualifiers(ParsedAttributes &Attrs);
-  /// Parses opencl_unroll_hint attribute if language is OpenCL v2.0
-  /// or higher.
-  /// \return false if error happens.
-  bool MaybeParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs) {
-    if (getLangOpts().OpenCL)
-      return ParseOpenCLUnrollHintAttribute(Attrs);
-    return true;
-  }
-  /// Parses opencl_unroll_hint attribute.
-  /// \return false if error happens.
-  bool ParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs);
   void ParseNullabilityTypeSpecifiers(ParsedAttributes &attrs);
 
   VersionTuple ParseVersionTuple(SourceRange &Range);
Index: clang/lib/Parse/ParseStmt.cpp
===================================================================
--- clang/lib/Parse/ParseStmt.cpp
+++ clang/lib/Parse/ParseStmt.cpp
@@ -98,10 +98,15 @@
 
   ParenBraceBracketBalancer BalancerRAIIObj(*this);
 
+  // Because we're parsing either a statement or a declaration, the order of
+  // attribute parsing is important. [[]] attributes at the start of a
+  // statement are different from [[]] attributes that follow an __attribute__
+  // at the start of the statement. Thus, we're not using MaybeParseAttributes
+  // here because we don't want to allow arbitrary orderings.
   ParsedAttributesWithRange Attrs(AttrFactory);
   MaybeParseCXX11Attributes(Attrs, nullptr, /*MightBeObjCMessageSend*/ true);
-  if (!MaybeParseOpenCLUnrollHintAttribute(Attrs))
-    return StmtError();
+  if (getLangOpts().OpenCL)
+    MaybeParseGNUAttributes(Attrs);
 
   StmtResult Res = ParseStatementOrDeclarationAfterAttributes(
       Stmts, StmtCtx, TrailingElseLoc, Attrs);
@@ -2548,19 +2553,3 @@
   }
   Braces.consumeClose();
 }
-
-bool Parser::ParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs) {
-  MaybeParseGNUAttributes(Attrs);
-
-  if (Attrs.empty())
-    return true;
-
-  if (Attrs.begin()->getKind() != ParsedAttr::AT_OpenCLUnrollHint)
-    return true;
-
-  if (!(Tok.is(tok::kw_for) || Tok.is(tok::kw_while) || Tok.is(tok::kw_do))) {
-    Diag(Tok, diag::err_opencl_unroll_hint_on_non_loop);
-    return false;
-  }
-  return true;
-}
Index: clang/lib/Sema/SemaStmtAttr.cpp
===================================================================
--- clang/lib/Sema/SemaStmtAttr.cpp
+++ clang/lib/Sema/SemaStmtAttr.cpp
@@ -378,6 +378,12 @@
   // determines unrolling factor) or 1 argument (the unroll factor provided
   // by the user).
 
+  if (!isa<ForStmt, CXXForRangeStmt, DoStmt, WhileStmt>(St)) {
+    S.Diag(A.getLoc(), diag::err_attribute_wrong_decl_type_str)
+        << A << "'for', 'while', and 'do' statements";
+    return nullptr;
+  }
+
   unsigned NumArgs = A.getNumArgs();
 
   if (NumArgs > 1) {
Index: clang/test/Parser/opencl-unroll-hint.cl
===================================================================
--- clang/test/Parser/opencl-unroll-hint.cl
+++ clang/test/Parser/opencl-unroll-hint.cl
@@ -1,8 +1,21 @@
-//RUN: %clang_cc1 -O0 -cl-std=CL2.0 -fsyntax-only -verify %s
+//RUN: %clang_cc1 -cl-std=CL2.0 -fsyntax-only -verify %s
 
 kernel void B (global int *x) {
-  __attribute__((opencl_unroll_hint(42)))
-  if (x[0])                             // expected-error {{OpenCL only supports 'opencl_unroll_hint' attribute on for, while, and do statements}}
+  __attribute__((opencl_unroll_hint(42))) // expected-error {{'opencl_unroll_hint' attribute only applies to 'for', 'while', and 'do' statements}}
+  if (x[0])
     x[0] = 15;
 }
 
+void parse_order_error() {
+  // Ensure we properly diagnose OpenCL loop attributes on the incorrect
+  // subject in the presence of other attributes.
+  int i = 1000;
+  __attribute__((nomerge, opencl_unroll_hint(8))) // expected-error {{'opencl_unroll_hint' attribute only applies to 'for', 'while', and 'do' statements}}
+  if (i) { parse_order_error(); } // Recursive call silences unrelated diagnostic about nomerge.
+
+  __attribute__((opencl_unroll_hint(8), nomerge)) // expected-error {{'opencl_unroll_hint' attribute only applies to 'for', 'while', and 'do' statements}}
+  if (i) { parse_order_error(); } // Recursive call silences unrelated diagnostic about nomerge.
+
+  __attribute__((nomerge, opencl_unroll_hint(8))) // OK
+  while (1) { parse_order_error(); } // Recursive call silences unrelated diagnostic about nomerge.
+}