diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 18a041d7a72ab..bdbf1891190e4 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -2076,7 +2076,8 @@ TypeInfo ASTContext::getTypeInfoImpl(const Type *T) const {
     TypeInfo EltInfo = getTypeInfo(VT->getElementType());
     Width = VT->isExtVectorBoolType() ? VT->getNumElements()
                                       : EltInfo.Width * VT->getNumElements();
-    // Enforce at least byte alignment.
+    // Enforce at least byte size and alignment.
+    Width = std::max<unsigned>(8, Width);
     Align = std::max<unsigned>(8, Width);
 
     // If the alignment is not a power of 2, round up to the next power of 2.
diff --git a/clang/test/SemaCXX/vector-bool.cpp b/clang/test/SemaCXX/vector-bool.cpp
index 1b83a20999cb2..e99d420e73fab 100644
--- a/clang/test/SemaCXX/vector-bool.cpp
+++ b/clang/test/SemaCXX/vector-bool.cpp
@@ -90,3 +90,25 @@ bool* ElementRefs() {
   foo(eight_bools.w);    // expected-error@90 {{illegal vector component name ''w''}}
   foo(eight_bools.wyx);  // expected-error@91 {{illegal vector component name ''wyx''}}
 }
+
+void Sizeof() {
+  using FourBools = bool __attribute__((ext_vector_type(4)));
+  using NineBools = bool __attribute__((ext_vector_type(9)));
+  using TwentyEightBools = bool __attribute__((ext_vector_type(28)));
+  using ThirtyThreeBools = bool __attribute__((ext_vector_type(33)));
+  using SixtyFiveBools = bool __attribute__((ext_vector_type(65)));
+  using Bool129 = bool __attribute__((ext_vector_type(129)));
+  using Bool150 = bool __attribute__((ext_vector_type(150)));
+  using Bool195 = bool __attribute__((ext_vector_type(195)));
+  using Bool257 = bool __attribute__((ext_vector_type(257)));
+  static_assert(sizeof(FourBools) == 1);
+  static_assert(sizeof(EightBools) == 1);
+  static_assert(sizeof(NineBools) == 2);
+  static_assert(sizeof(TwentyEightBools) == 4);
+  static_assert(sizeof(ThirtyThreeBools) == 8);
+  static_assert(sizeof(SixtyFiveBools) == 16);
+  static_assert(sizeof(Bool129) == 32);
+  static_assert(sizeof(Bool150) == 32);
+  static_assert(sizeof(Bool195) == 32);
+  static_assert(sizeof(Bool257) == 64);
+}