[ECOS] 64 bit c-pointers

Gary Thomas gary@mlbassoc.com
Mon Oct 27 15:23:00 GMT 2003


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Rini van Zetten said:
> Hi Gary,
>
> Thanks for your answer.
>
> But i still have some doubts.
>
> If you look for example at the file hal_if.c in packages/common/v2_0/src
> you see
>
>         for (i = 0; i < CYGNUM_CALL_IF_TABLE_SIZE; i++)
>             hal_virtual_vector_table[i] = (CYG_ADDRWORD) &nop_service;
>
> where IMHO an address is forced to 32 bit isn't it ?

Not in a properly defined HAL!  CYG_ADDRWORD is defined to be a quantity
large enough to hold any arbitrary pointer.  If your hardware has 64 bit
addresses, then this must be defined as so.

Note 1: this is not what your original question asked (but I'm sure it's
what you wanted to know).

Note 2: AFAIK, eCos has never been ported to a pure 64 bit system, only
some hybrids which can be configured as either 32 or 64.  I'm sure that
there are some places in the code where there may be problems when moving
to a 64-bit address space.

>
> Rini
>
> ----- Original Message -----
> From: "Gary Thomas" <gary@mlbassoc.com>
> To: "ARVOO support" <support@arvoo.nl>
> Cc: <ecos-discuss@sources.redhat.com>
> Sent: Monday, October 27, 2003 3:44 PM
> Subject: Re: [ECOS] 64 bit c-pointers
>
>
>>
>> ARVOO support said:
>> > Hi All,
>> >
>> > Is it possible to use 64 bit pointers in ecos c-code ?
>> > eg
>> >
>> > int *p;
>> >
>> > where sizeof(p) results in 8
>> >
>>
>> It depends on the compiler and target architecture - eCos doesn't care
>>
>
>


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