diff --git a/clang/docs/LanguageExtensions.rst b/clang/docs/LanguageExtensions.rst
--- a/clang/docs/LanguageExtensions.rst
+++ b/clang/docs/LanguageExtensions.rst
@@ -478,7 +478,7 @@
 !, &&, ||                        yes     --        yes [#]_    --
 ==, !=, >, <, >=, <=             yes     yes       yes         --
 =                                yes     yes       yes         yes
-:? [#]_                          yes     --        yes         --
+?: [#]_                          yes     --        yes         --
 sizeof                           yes     yes       yes         yes
 C-style cast                     yes     yes       yes         no
 reinterpret_cast                 yes     no        yes         no
@@ -489,9 +489,11 @@
 See also :ref:`langext-__builtin_shufflevector`, :ref:`langext-__builtin_convertvector`.
 
 .. [#] unary operator ! is not implemented, however && and || are.
-.. [#] While OpenCL and GCC vectors both implement the comparison operator(?:) as a
-  'select', they operate somewhat differently. OpenCL selects based on signedness of
-  the condition operands, but GCC vectors use normal bool conversions (that is, != 0).
+.. [#] ternary operator(?:) has different behaviors depending on condition
+  operand's vector type. If the condition is a GNU vector (i.e. __vector_size__),
+  it's only available in C++ and uses normal bool conversions (that is, != 0).
+  If it's an extension (OpenCL) vector, it's only available in C and OpenCL C.
+  And it selects base on signedness of the condition operands (OpenCL v1.1 s6.3.9).
 
 Matrix Types
 ============
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -4432,8 +4432,8 @@
 
   // OpenCL: If the condition is a vector, we can treat this condition like
   // the select function.
-  if (CGF.getLangOpts().OpenCL
-      && condExpr->getType()->isVectorType()) {
+  if ((CGF.getLangOpts().OpenCL && condExpr->getType()->isVectorType()) ||
+      condExpr->getType()->isExtVectorType()) {
     CGF.incrementProfileCounter(E);
 
     llvm::Value *CondV = CGF.EmitScalarExpr(condExpr);
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -8078,7 +8078,8 @@
 
   // The OpenCL operator with a vector condition is sufficiently
   // different to merit its own checker.
-  if (getLangOpts().OpenCL && Cond.get()->getType()->isVectorType())
+  if ((getLangOpts().OpenCL && Cond.get()->getType()->isVectorType()) ||
+      Cond.get()->getType()->isExtVectorType())
     return OpenCLCheckVectorConditional(*this, Cond, LHS, RHS, QuestionLoc);
 
   // First, check the condition.
diff --git a/clang/test/Sema/ext_vector_comparisons.c b/clang/test/Sema/ext_vector_comparisons.c
--- a/clang/test/Sema/ext_vector_comparisons.c
+++ b/clang/test/Sema/ext_vector_comparisons.c
@@ -28,3 +28,19 @@
   return vec > vec;  // no-warning
   return vec >= vec; // no-warning
 }
+
+static int4 test3() {
+  int4 i0, i1;
+
+  return i0 > i1 ? i0 : i1; // no-error
+  return i0 ? i0 : i1;      // no-error
+}
+
+static float4 test4() {
+  float4 f0, f1;
+
+  // This would actually generate implicit casting warning
+  // under Weverything flag but we don't really care here
+  return f0 > f1 ? f0 : f1; // no-error
+  return f0 ? f0 : f1;      // expected-error {{used type 'float4' (vector of 4 'float' values) where floating point type is not allowed}}
+}