On 06.03.2023 08:21, Juergen Gross wrote:
> --- a/tools/include/xen-tools/common-macros.h
> +++ b/tools/include/xen-tools/common-macros.h
> @@ -80,4 +80,8 @@
> typeof( ((type *)0)->member ) *__mptr = (ptr); \
> (type *)( (char *)__mptr - offsetof(type,member) );})
>
> +#ifndef offsetof
> +#define offsetof(a, b) __builtin_offsetof(a, b)
> +#endif
How's this going to work reliably with parties perhaps also including
stddef.h, which also is expected to define this macro, and which may
do so with a different sequence of tokens (even if that ends up
having the same effect)? There shouldn't be a need to define this
macro for any "normal" environments, e.g. ...
> --- a/tools/libfsimage/xfs/fsys_xfs.c
> +++ b/tools/libfsimage/xfs/fsys_xfs.c
> @@ -19,6 +19,7 @@
>
> #include <xenfsimage_grub.h>
> #include "xfs.h"
> +#include <xen-tools/common-macros.h>
>
> #define MAX_LINK_COUNT 8
>
> @@ -182,9 +183,6 @@ fsb2daddr (xfs_fsblock_t fsbno)
> (xfs_agblock_t)(fsbno & mask32lo(xfs.agblklog)));
> }
>
> -#undef offsetof
> -#define offsetof(t,m) ((size_t)&(((t *)0)->m))
> -
> static inline int
> btroot_maxrecs (fsi_file_t *ffi)
> {
... this library or ...
> --- a/tools/libs/vchan/init.c
> +++ b/tools/libs/vchan/init.c
> @@ -69,10 +69,6 @@
> #define MAX_RING_SHIFT 20
> #define MAX_RING_SIZE (1 << MAX_RING_SHIFT)
>
> -#ifndef offsetof
> -#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
> -#endif
> -
> static int init_gnt_srv(struct libxenvchan *ctrl, int domain)
> {
> int pages_left = ctrl->read.order >= PAGE_SHIFT ? 1 <<
> (ctrl->read.order - PAGE_SHIFT) : 0;
... this tool or ...
> --- a/tools/tests/vhpet/emul.h
> +++ b/tools/tests/vhpet/emul.h
> @@ -115,8 +115,6 @@ enum
> NR_COMMON_SOFTIRQS
> };
>
> -#define offsetof(t, m) ((unsigned long )&((t *)0)->m)
> -
> struct domain;
>
> struct vcpu
... this test binary (which is an ordinary host one as well). They all
should include stddef.h and be done.
Jan
