[PATCH] abstract away from the 'build-toolchain'-dependent sizeof(...) operator

[Simon Marlow]

On 05/01/2012 18:41, Gabor Greif wrote:
> The sizes obtained this way do not work on a target system in general.
> So in a future cross-compilable setup we need another way of obtaining
> expansions for the macros OFFSET, FIELD_SIZE and TYPE_SIZE.
>
> Guarded against accidental use of 'sizeof' by poisoning.
>
> Verified that the generated *Constants.h/hs files are unchanged.

Ok, I'll push this one.

Cheers,
	Simon



> ---
>   includes/mkDerivedConstants.c |   24 ++++++++++++++----------
>   1 files changed, 14 insertions(+), 10 deletions(-)
>
> diff --git a/includes/mkDerivedConstants.c b/includes/mkDerivedConstants.c
> index 6688330..8d2e789 100644
> --- a/includes/mkDerivedConstants.c
> +++ b/includes/mkDerivedConstants.c
> @@ -1,6 +1,6 @@
>   /* --------------------------------------------------------------------------
>    *
> - * (c) The GHC Team, 1992-2004
> + * (c) The GHC Team, 1992-2012
>    *
>    * mkDerivedConstants.c
>    *
> @@ -17,11 +17,11 @@
>    * We need offsets of profiled things... better be careful that this
>    * doesn't affect the offsets of anything else.
>    */
> +
>   #define PROFILING
>   #define THREADED_RTS
>
>   #include "Rts.h"
> -
>   #include "Stable.h"
>   #include "Capability.h"
>
> @@ -30,6 +30,10 @@
>   #define str(a,b) #a "_" #b
>
>   #define OFFSET(s_type, field) ((size_t)&(((s_type*)0)->field))
> +#define FIELD_SIZE(s_type, field) ((unsigned long)sizeof(((s_type*)0)->field))
> +#define TYPE_SIZE(type) (sizeof(type))
> +
> +#pragma GCC poison sizeof
>
>   #if defined(GEN_HASKELL)
>   #define def_offset(str, offset)                          \
> @@ -44,7 +48,7 @@
>   #define ctype(type) /* nothing */
>   #else
>   #define ctype(type) \
> -    printf("#define SIZEOF_" #type " %lu\n", (unsigned long)sizeof(type));
> +    printf("#define SIZEOF_" #type " %lu\n", (unsigned long)TYPE_SIZE(type));
>   #endif
>
>   #if defined(GEN_HASKELL)
> @@ -59,7 +63,7 @@
>   */
>   #define field_type_(str, s_type, field) \
>       printf("#define REP_" str " b"); \
> -    printf("%lu\n", (unsigned long)sizeof (__typeof__(((((s_type*)0)->field)))) * 8);
> +    printf("%lu\n", FIELD_SIZE(s_type, field) * 8);
>   #define field_type_gcptr_(str, s_type, field) \
>       printf("#define REP_" str " gcptr\n");
>   #endif
> @@ -105,18 +109,18 @@
>   #endif
>
>   #define struct_size(s_type) \
> -    def_size(#s_type, sizeof(s_type));
> +    def_size(#s_type, TYPE_SIZE(s_type));
>
>   /*
>    * Size of a closure type, minus the header, named SIZEOF_<type>_NoHdr
>    * Also, we #define SIZEOF_<type>  to be the size of the whole closure for .cmm.
>    */
>   #define closure_size(s_type) \
> -    def_size(#s_type "_NoHdr", sizeof(s_type) - sizeof(StgHeader)); \
> -    def_closure_size(#s_type, sizeof(s_type) - sizeof(StgHeader));
> +    def_size(#s_type "_NoHdr", TYPE_SIZE(s_type) - TYPE_SIZE(StgHeader)); \
> +    def_closure_size(#s_type, TYPE_SIZE(s_type) - TYPE_SIZE(StgHeader));
>
>   #define thunk_size(s_type) \
> -    def_size(#s_type "_NoThunkHdr", sizeof(s_type) - sizeof(StgThunkHeader)); \
> +    def_size(#s_type "_NoThunkHdr", TYPE_SIZE(s_type) - TYPE_SIZE(StgThunkHeader)); \
>       closure_size(s_type)
>
>   /* An access macro for use in C-- sources. */
> @@ -124,7 +128,7 @@
>       printf("#define " str "(__ptr__)  REP_" str "[__ptr__+SIZEOF_StgHeader+OFFSET_" str "]\n");
>
>   #define closure_field_offset_(str, s_type,field) \
> -    def_offset(str, OFFSET(s_type,field) - sizeof(StgHeader));
> +    def_offset(str, OFFSET(s_type,field) - TYPE_SIZE(StgHeader));
>
>   #define closure_field_offset(s_type,field) \
>       closure_field_offset_(str(s_type,field),s_type,field)
> @@ -156,7 +160,7 @@
>
>   /* Byte offset for a TSO field, minus the header and variable prof bit. */
>   #define tso_payload_offset(s_type, field) \
> -    def_offset(str(s_type,field), OFFSET(s_type,field) - sizeof(StgHeader) - sizeof(StgTSOProfInfo));
> +    def_offset(str(s_type,field), OFFSET(s_type,field) - TYPE_SIZE(StgHeader) - TYPE_SIZE(StgTSOProfInfo));
>
>   /* Full byte offset for a TSO field, for use from Cmm */
>   #define tso_field_offset_macro(str) \