Re: [Xen-devel] [patch] fix void* arithmetic

["Jan Beulich" <jbeulich@xxxxxxxxxx>]

>-#define ELFNOTE_NAME(_n_)   ((void*)(_n_) + sizeof(*(_n_)))
>-#define ELFNOTE_DESC(_n_)   (ELFNOTE_NAME(_n_) + (((_n_)->namesz+3)&~3))
>-#define ELFNOTE_NEXT(_n_)   (ELFNOTE_DESC(_n_) + (((_n_)->descsz+3)&~3))
>+#define ELFNOTE_NAME(_n_)   ((void*)((char*)(_n_) + sizeof(*(_n_))))
>+#define ELFNOTE_DESC(_n_)   (((void*)((char*)ELFNOTE_NAME(_n_) + 
>(((_n_)->namesz+3)&~3))))
>+#define ELFNOTE_NEXT(_n_)   (((void*)((char*)ELFNOTE_DESC(_n_) + 
>(((_n_)->descsz+3)&~3))))

This seems to complicate it a little too much, eg it would seem that this

#define ELFNOTE_NAME(_n_)   ((char *)(_n_) + sizeof(*(_n_)))
#define ELFNOTE_DESC(_n_)   (ELFNOTE_NAME(_n_) + (((_n_)->namesz+3)&~3))
#define ELFNOTE_NEXT(_n_)   ((Elf_Note *)(ELFNOTE_DESC(_n_) + 
(((_n_)->descsz+3)&~3)))

would also do, and would even allow dropping an odd cast in the return statement
of xen_elfnote_string().

Jan

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