Re: [PATCH v3 5/5] tools/ocaml: Fix redefinition errors

[Julien Grall <julien@xen.org>]

Hi Costin,

On 10/05/2021 09:35, Costin Lupu wrote:
> If PAGE_SIZE is already defined in the system (e.g. in /usr/include/limits.h
> header) then gcc will trigger a redefinition error because of -Werror. This
> patch replaces usage of PAGE_* macros with XC_PAGE_* macros in order to avoid
> confusion between control domain page granularity (PAGE_* definitions) and
> guest domain page granularity (which is what we are dealing with here).
> 
> Same issue applies for redefinitions of Val_none and Some_val macros which
> can be already define in the OCaml system headers (e.g.
> /usr/lib/ocaml/caml/mlvalues.h).
> 
> Signed-off-by: Costin Lupu <costin.lupu@cs.pub.ro>

Reviewed-by: Julien Grall <jgrall@amazon.com>

Cheers,

> ---
>   tools/ocaml/libs/xc/xenctrl_stubs.c            | 10 ++++------
>   tools/ocaml/libs/xentoollog/xentoollog_stubs.c |  4 ++++
>   tools/ocaml/libs/xl/xenlight_stubs.c           |  4 ++++
>   3 files changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/tools/ocaml/libs/xc/xenctrl_stubs.c b/tools/ocaml/libs/xc/xenctrl_stubs.c
> index d05d7bb30e..f9e33e599a 100644
> --- a/tools/ocaml/libs/xc/xenctrl_stubs.c
> +++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
> @@ -36,14 +36,12 @@
>   
>   #include "mmap_stubs.h"
>   
> -#define PAGE_SHIFT		12
> -#define PAGE_SIZE               (1UL << PAGE_SHIFT)
> -#define PAGE_MASK               (~(PAGE_SIZE-1))
> -
>   #define _H(__h) ((xc_interface *)(__h))
>   #define _D(__d) ((uint32_t)Int_val(__d))
>   
> +#ifndef Val_none
>   #define Val_none (Val_int(0))
> +#endif
>   
>   #define string_of_option_array(array, index) \
>   	((Field(array, index) == Val_none) ? NULL : String_val(Field(Field(array, index), 0)))
> @@ -818,7 +816,7 @@ CAMLprim value stub_xc_domain_memory_increase_reservation(value xch,
>   	CAMLparam3(xch, domid, mem_kb);
>   	int retval;
>   
> -	unsigned long nr_extents = ((unsigned long)(Int64_val(mem_kb))) >> (PAGE_SHIFT - 10);
> +	unsigned long nr_extents = ((unsigned long)(Int64_val(mem_kb))) >> (XC_PAGE_SHIFT - 10);
>   
>   	uint32_t c_domid = _D(domid);
>   	caml_enter_blocking_section();
> @@ -924,7 +922,7 @@ CAMLprim value stub_pages_to_kib(value pages)
>   {
>   	CAMLparam1(pages);
>   
> -	CAMLreturn(caml_copy_int64(Int64_val(pages) << (PAGE_SHIFT - 10)));
> +	CAMLreturn(caml_copy_int64(Int64_val(pages) << (XC_PAGE_SHIFT - 10)));
>   }
>   
>   
> diff --git a/tools/ocaml/libs/xentoollog/xentoollog_stubs.c b/tools/ocaml/libs/xentoollog/xentoollog_stubs.c
> index bf64b211c2..e4306a0c2f 100644
> --- a/tools/ocaml/libs/xentoollog/xentoollog_stubs.c
> +++ b/tools/ocaml/libs/xentoollog/xentoollog_stubs.c
> @@ -53,8 +53,12 @@ static char * dup_String_val(value s)
>   #include "_xtl_levels.inc"
>   
>   /* Option type support as per http://www.linux-nantes.org/~fmonnier/ocaml/ocaml-wrapping-c.php */
> +#ifndef Val_none
>   #define Val_none Val_int(0)
> +#endif
> +#ifndef Some_val
>   #define Some_val(v) Field(v,0)
> +#endif
>   
>   static value Val_some(value v)
>   {
> diff --git a/tools/ocaml/libs/xl/xenlight_stubs.c b/tools/ocaml/libs/xl/xenlight_stubs.c
> index 352a00134d..45b8af61c7 100644
> --- a/tools/ocaml/libs/xl/xenlight_stubs.c
> +++ b/tools/ocaml/libs/xl/xenlight_stubs.c
> @@ -227,8 +227,12 @@ static value Val_string_list(libxl_string_list *c_val)
>   }
>   
>   /* Option type support as per http://www.linux-nantes.org/~fmonnier/ocaml/ocaml-wrapping-c.php */
> +#ifndef Val_none
>   #define Val_none Val_int(0)
> +#endif
> +#ifndef Some_val
>   #define Some_val(v) Field(v,0)
> +#endif
>   
>   static value Val_some(value v)
>   {
> 

-- 
Julien Grall