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How to stop gcc padding structs???

I'm again fighting with gcc trying (and failing) to get it to
stop putting padding bytes into structs.  Has anybody figured
out how to prevent gcc from padding structs?

I ran into this problem before and gave up, finally having to
use hand-calculated constants instead of "sizeof (struct foo)"
in numerous places.  For example, it's impossible to define an
Ethernet header structure that ends up having a size of 14

In the following example, gcc insists that each of the "high"
structs occupies four bytes despite my putting a "packed"
attribute evryplace that doesn't generate a syntax warning.

$ arm-elf-gcc -v   
Reading specs from /usr/local/lib/gcc-lib/arm-elf/2.95.2/specs
gcc version 2.95.2 19991024 (release)

typedef struct
  volatile unsigned char data __attribute__((packed));
  volatile unsigned char _xxx __attribute__((packed));
} high __attribute((packed));

typedef struct
  high  a __attribute__((packed));
  high  b __attribute__((packed));
  high  c __attribute__((packed));
} tDemo __attribute__((packed));

tDemo foo;

void *addr[] =

testit:     file format elf32-bigarm
Disassembly of section .data:
00008000 <addr>:
    8000:	00008010
    8004:	00008010
    8008:	00008014
    800c:	00008018

Grant Edwards

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