diff --git a/clang/lib/CodeGen/CodeGenTypes.cpp b/clang/lib/CodeGen/CodeGenTypes.cpp
index d431c0263666ea..cad63fee45703f 100644
--- a/clang/lib/CodeGen/CodeGenTypes.cpp
+++ b/clang/lib/CodeGen/CodeGenTypes.cpp
@@ -93,7 +93,8 @@ llvm::Type *CodeGenTypes::ConvertTypeForMem(QualType T, bool ForBitField) {
 
   // If this is a bool type, or an ExtIntType in a bitfield representation,
   // map this integer to the target-specified size.
-  if ((ForBitField && T->isExtIntType()) || R->isIntegerTy(1))
+  if ((ForBitField && T->isExtIntType()) ||
+      (!T->isExtIntType() && R->isIntegerTy(1)))
     return llvm::IntegerType::get(getLLVMContext(),
                                   (unsigned)Context.getTypeSize(T));
 
diff --git a/clang/test/CodeGen/ext-int.c b/clang/test/CodeGen/ext-int.c
index 196bb810b61ab5..d8e763283bfd95 100644
--- a/clang/test/CodeGen/ext-int.c
+++ b/clang/test/CodeGen/ext-int.c
@@ -45,3 +45,16 @@ void OffsetOfTest() {
   // LIN32: store i32 2097156, i32* %{{.+}}
   // WIN32: store i32 2097160, i32* %{{.+}}
 }
+
+void Size1ExtIntParam(unsigned _ExtInt(1) A) {
+  // CHECK: define {{.*}}void @Size1ExtIntParam(i1{{.*}}  %[[PARAM:.+]])
+  // CHECK: %[[PARAM_ADDR:.+]] = alloca i1
+  // CHECK: %[[B:.+]] = alloca [5 x i1]
+  // CHECK: store i1 %[[PARAM]], i1* %[[PARAM_ADDR]]
+  unsigned _ExtInt(1) B[5];
+
+  // CHECK: %[[PARAM_LOAD:.+]] = load i1, i1* %[[PARAM_ADDR]]
+  // CHECK: %[[IDX:.+]] = getelementptr inbounds [5 x i1], [5 x i1]* %[[B]]
+  // CHECK: store i1 %[[PARAM_LOAD]], i1* %[[IDX]]
+  B[2] = A;
+}