diff --git a/clang/lib/Basic/Targets/AVR.cpp b/clang/lib/Basic/Targets/AVR.cpp
--- a/clang/lib/Basic/Targets/AVR.cpp
+++ b/clang/lib/Basic/Targets/AVR.cpp
@@ -309,6 +309,8 @@
   Builder.defineMacro("__AVR__");
   Builder.defineMacro("__ELF__");
   Builder.defineMacro("__flash", "__attribute__((address_space(1)))");
+  Builder.defineMacro("__UINT16_TYPE__", "unsigned int");
+  Builder.defineMacro("__INT16_TYPE__", "int");
 
   if (!this->CPU.empty()) {
     auto It = llvm::find_if(
diff --git a/clang/test/CodeGen/builtins.cpp b/clang/test/CodeGen/builtins.cpp
--- a/clang/test/CodeGen/builtins.cpp
+++ b/clang/test/CodeGen/builtins.cpp
@@ -1,6 +1,5 @@
 // RUN: %clang_cc1 -std=c++11 -triple x86_64-linux-gnu -ffreestanding -verify %s
 // RUN: %clang_cc1 -std=c++11 -triple i686-pc-linux-gnu -ffreestanding -verify %s
-// RUN: %clang_cc1 -std=c++11 -triple avr-unknown-unknown -ffreestanding -verify %s
 
 // expected-no-diagnostics
 
diff --git a/clang/test/Preprocessor/init.c b/clang/test/Preprocessor/init.c
--- a/clang/test/Preprocessor/init.c
+++ b/clang/test/Preprocessor/init.c
@@ -1942,7 +1942,7 @@
 // AVR:#define __GXX_ABI_VERSION 1002
 // AVR:#define __INT16_C_SUFFIX__
 // AVR:#define __INT16_MAX__ 32767
-// AVR:#define __INT16_TYPE__ short
+// AVR:#define __INT16_TYPE__ int
 // AVR:#define __INT32_C_SUFFIX__ L
 // AVR:#define __INT32_MAX__ 2147483647L
 // AVR:#define __INT32_TYPE__ long int
@@ -2017,7 +2017,7 @@
 // AVR:#define __SIZE_TYPE__ unsigned int
 // AVR:#define __STDC__ 1
 // AVR:#define __UINT16_MAX__ 65535U
-// AVR:#define __UINT16_TYPE__ unsigned short
+// AVR:#define __UINT16_TYPE__ unsigned int
 // AVR:#define __UINT32_C_SUFFIX__ UL
 // AVR:#define __UINT32_MAX__ 4294967295UL
 // AVR:#define __UINT32_TYPE__ long unsigned int