1 files changed, 29 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaExprMember.cpp b/clang/lib/Sema/SemaExprMember.cpp
index 283621889f8..0c625b24c57 100644
--- a/clang/lib/Sema/SemaExprMember.cpp
+++ b/clang/lib/Sema/SemaExprMember.cpp
@@ -269,6 +269,20 @@ Sema::BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS,
   llvm_unreachable("unexpected instance member access kind");
 }
 
+/// Determine whether input char is from rgba component set.
+static bool
+IsRGBA(char c) {
+  switch (c) {
+  case 'r':
+  case 'g':
+  case 'b':
+  case 'a':
+    return true;
+  default:
+    return false;
+  }
+}
+
 /// Check an ext-vector component access expression.
 ///
 /// VK should be set in advance to the value kind of the base
@@ -308,11 +322,25 @@ CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK,
     HalvingSwizzle = true;
   } else if (!HexSwizzle &&
              (Idx = vecType->getPointAccessorIdx(*compStr)) != -1) {
+    bool HasRGBA = IsRGBA(*compStr);
     do {
+      // Ensure that xyzw and rgba components don't intermingle.
+      if (HasRGBA != IsRGBA(*compStr))
+        break;
       if (HasIndex[Idx]) HasRepeated = true;
       HasIndex[Idx] = true;
       compStr++;
     } while (*compStr && (Idx = vecType->getPointAccessorIdx(*compStr)) != -1);
+
+    // Emit a warning if an rgba selector is used earlier than OpenCL 2.2
+    if (HasRGBA || (*compStr && IsRGBA(*compStr))) {
+      if (S.getLangOpts().OpenCL && S.getLangOpts().OpenCLVersion < 220) {
+        const char *DiagBegin = HasRGBA ? CompName->getNameStart() : compStr;
+        S.Diag(OpLoc, diag::ext_opencl_ext_vector_type_rgba_selector)
+          << StringRef(DiagBegin, 1)
+          << S.getLangOpts().OpenCLVersion << SourceRange(CompLoc);
+      }
+    }
   } else {
     if (HexSwizzle) compStr++;
     while ((Idx = vecType->getNumericAccessorIdx(*compStr)) != -1) {
@@ -339,7 +367,7 @@ CheckExtVectorComponent(Sema &S, QualType baseType, ExprValueKind &VK,
       compStr++;
 
     while (*compStr) {
-      if (!vecType->isAccessorWithinNumElements(*compStr++)) {
+      if (!vecType->isAccessorWithinNumElements(*compStr++, HexSwizzle)) {
         S.Diag(OpLoc, diag::err_ext_vector_component_exceeds_length)
           << baseType << SourceRange(CompLoc);
         return QualType();