-#define FFS_FILE_SIZE(FfsFileHeaderPtr) \\r
- ((UINT32) (*((UINT32 *) ((EFI_FFS_FILE_HEADER *) (UINTN) FfsFileHeaderPtr)->Size) & 0x00ffffff))\r
+///\r
+/// The argument passed as the FfsFileHeaderPtr parameter to the\r
+/// FFS_FILE_SIZE() function-like macro below must not have side effects:\r
+/// FfsFileHeaderPtr is evaluated multiple times.\r
+///\r
+#define FFS_FILE_SIZE(FfsFileHeaderPtr) ((UINT32) ( \\r
+ (((EFI_FFS_FILE_HEADER *) (UINTN) (FfsFileHeaderPtr))->Size[0] ) | \\r
+ (((EFI_FFS_FILE_HEADER *) (UINTN) (FfsFileHeaderPtr))->Size[1] << 8) | \\r
+ (((EFI_FFS_FILE_HEADER *) (UINTN) (FfsFileHeaderPtr))->Size[2] << 16)))\r