diff --git a/include/llvm/Support/DataTypes.h.in b/include/llvm/Support/DataTypes.h.in
index f16a2cd9a29..26a0873151b 100644
--- a/include/llvm/Support/DataTypes.h.in
+++ b/include/llvm/Support/DataTypes.h.in
@@ -63,6 +63,18 @@ typedef u_int64_t uint64_t;
 #endif
 #endif
 
+#ifdef _OpenBSD_
+#define INT8_MAX 127
+#define INT8_MIN -128
+#define UINT8_MAX 255
+#define INT16_MAX 32767
+#define INT16_MIN -32768
+#define UINT16_MAX 65535
+#define INT32_MAX 2147483647
+#define INT32_MIN -2147483648
+#define UINT32_MAX 4294967295U
+#endif
+
 #else /* _MSC_VER */
 // Visual C++ doesn't provide standard integer headers, but it does provide
 // built-in data types.