diff --git a/include/my_global.h b/include/my_global.h
index dce38a124c1..0c15478439f 100644
--- a/include/my_global.h
+++ b/include/my_global.h
@@ -857,8 +857,7 @@ typedef long long	my_ptrdiff_t;
   and related routines are refactored.
 */
 
-#define my_offsetof(TYPE, MEMBER) \
-        ((size_t)((char *)&(((TYPE *)0x10)->MEMBER) - (char*)0x10))
+#define my_offsetof(TYPE, MEMBER) PTR_BYTE_DIFF(&((TYPE *)0x10)->MEMBER, 0x10)
 
 #define NullS		(char *) 0
 
diff --git a/sql/parse_file.h b/sql/parse_file.h
index 2a0266e98b7..83a8eabcf5f 100644
--- a/sql/parse_file.h
+++ b/sql/parse_file.h
@@ -42,9 +42,9 @@ enum file_opt_type {
 
 struct File_option
 {
-  LEX_STRING name;		/**< Name of the option */
-  int offset;			/**< offset to base address of value */
-  file_opt_type type;		/**< Option type */
+  LEX_STRING name;              /**< Name of the option */
+  my_ptrdiff_t offset;          /**< offset to base address of value */
+  file_opt_type type;           /**< Option type */
 };