Include stddef.h in device_functions.h and remove use of uint8_t

[ROCm/hip commit: e22c35e124]

projects/hip/include/hip/hcc_detail/device_functions.h

@@ -26,6 +26,7 @@ THE SOFTWARE.
 #include "host_defines.h"
 
 #include <hip/hip_vector_types.h>
+#include <stddef.h>
 
 extern "C" __device__ unsigned int __hip_hc_ir_umul24_int(unsigned int, unsigned int);
 extern "C" __device__ signed int __hip_hc_ir_mul24_int(signed int, signed int);
@@ -212,8 +213,8 @@ __device__ char4 __hip_hc_mul8pk(char4, char4);
 
 // loop unrolling
 static inline __device__ void* __hip_hc_memcpy(void* dst, const void* src, size_t size) {
-    auto dstPtr = static_cast<uint8_t*>(dst);
-    auto srcPtr = static_cast<const uint8_t*>(src);
+    auto dstPtr = static_cast<unsigned char*>(dst);
+    auto srcPtr = static_cast<const unsigned char*>(src);
 
     while (size >= 4u) {
         dstPtr[0] = srcPtr[0];
@@ -237,8 +238,8 @@ static inline __device__ void* __hip_hc_memcpy(void* dst, const void* src, size_
     return dst;
 }
 
-static inline __device__ void* __hip_hc_memset(void* dst, uint8_t val, size_t size) {
-    auto dstPtr = static_cast<uint8_t*>(dst);
+static inline __device__ void* __hip_hc_memset(void* dst, unsigned char val, size_t size) {
+    auto dstPtr = static_cast<unsigned char*>(dst);
 
     while (size >= 4u) {
         dstPtr[0] = val;
@@ -265,7 +266,7 @@ static inline __device__ void* memcpy(void* dst, const void* src, size_t size) {
 }
 
 static inline __device__ void* memset(void* ptr, int val, size_t size) {
-    uint8_t val8 = static_cast<uint8_t>(val);
+    unsigned char val8 = static_cast<unsigned char>(val);
     return __hip_hc_memset(ptr, val8, size);
 }
 #endif