On our custom processor there is no constraint for short type variable
to align at 4 byte address, then how to resolve this issue.
Is there any compiler option available ?
Is it required to change port.h file ?
On 05/23/2014 04:11 PM, Jonathan Wakely wrote:
On 23 May 2014 11:06, Sivaprasad wrote:
I have a confusion about structure size calculation.
I have tried to compared structure size result with
gcc version 4.7.2 20121109 (Red Hat 4.7.2-8) generates code for x86 machine
and
cross compiler with gcc version 4.3.4 generate code for custom processor.
struct sample
{
short int s;
}a;
sizeof(a) showing 2 bytes with x86 gcc and 4 bytes with cross compiler.
struct sample
{
int i;
short int s;
}a;
sizeof(a) showing 8 bytes with x86 gcc and 8 bytes with cross compiler.
When compiler will add hole at end of the structure ?
To ensure that if you have an array of those objects the int member
will always be on a 4-byte boundary.
why cross compiler trying to make structure size multiple of 4 ?
Because GCC thinks short has an alignment of 4 on your custom processor.
