[fpc-pascal] alignment of records

[Xiangrong Fang]

Hi All,

I try to port a program from C to Pascal, see the following example:

#include <stdio.h>
#include <sys/socket.h>
#include <linux/if.h>
void main() {
    printf("ifmap=%ld\n", sizeof(struct ifmap));
}

I converted it to:

est.c  test.pas

       X
program test;
{$mode objfpc}{$PACKRECORDS C}
type
  ifmap = record
    mem_start: dword;
    mem_end: dword;
    base_addr: word;
    irq: byte;
    dma: byte;
    port: byte;
  end;
begin
  WriteLn('ifmap=', SizeOf(ifmap));
end.

The C struct's size is 24, but pascal record is 16.    The ifmap struct is
defined as:

struct ifmap {
    unsigned long mem_start;
    unsigned long mem_end;
    unsigned short base_addr;
    unsigned char irq;
    unsigned char dma;
    unsigned char port;
    /* 3 bytes spare */
};

How can I instruct FPC to align records exactly same as GCC?

Thanks!
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