Index: clang/lib/Sema/SemaType.cpp
===================================================================
--- clang/lib/Sema/SemaType.cpp
+++ clang/lib/Sema/SemaType.cpp
@@ -2517,9 +2517,10 @@
                                SourceLocation AttrLoc) {
   // The base type must be integer (not Boolean or enumeration) or float, and
   // can't already be a vector.
-  if (!CurType->isDependentType() &&
-      (!CurType->isBuiltinType() || CurType->isBooleanType() ||
-       (!CurType->isIntegerType() && !CurType->isRealFloatingType()))) {
+  if ((!CurType->isDependentType() &&
+       (!CurType->isBuiltinType() || CurType->isBooleanType() ||
+        (!CurType->isIntegerType() && !CurType->isRealFloatingType()))) ||
+      CurType->isArrayType()) {
     Diag(AttrLoc, diag::err_attribute_invalid_vector_type) << CurType;
     return QualType();
   }
Index: clang/test/SemaCXX/attr-gnu.cpp
===================================================================
--- clang/test/SemaCXX/attr-gnu.cpp
+++ clang/test/SemaCXX/attr-gnu.cpp
@@ -12,6 +12,13 @@
 
 void g(int a[static [[]] 5]); // expected-error {{static array size is a C99 feature, not permitted in C++}}
 
+template<typename T> struct A {
+  int x[sizeof(T)] __attribute((vector_size(8))); // expected-error {{invalid vector element type 'int [sizeof(T)]'}}
+};
+
+typedef int myvect[4] __attribute__((vector_size(16))); // expected-error {{invalid vector element type 'int [4]'}}
+void foo(myvect *in, myvect *out) { (*out)[0] = (*in)[0]; }
+
 namespace {
 class B {
 public: