From: Henno Vermeulen <Vermeulen AT regiolicht DOT nl>
Newsgroups: comp.os.msdos.djgpp
Subject: Char-in-struct bug!?
Date: Mon, 11 Jan 1999 21:44:33 +0100
Organization: Casema Internet
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To: djgpp AT delorie DOT com
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I found out, that when you use a struct with djgpp (both in .c and .cpp
files) like this:

typedef struct {
    char x, y, z;
  } my_type1;

the size will be 3 bytes, but when you have one like this:

typedef struct {
    char x, y, z;
    int i;
  } my_type2;

the size will be 8 bytes, even if I remove y or y and z. When I add a
char behind i, the size will grow to 12 bytes! When using short ints, I
get the same problem.

Is this some kind of dword/long int aligning? Or is it a bug?

I found this strange thing when I made a structure containing a .bmp
header, which uses as the first two bytes, the chars 'B' and 'M'.
Compiling with turbo c++ 3.0 gives a (correct) structure size of 54, but
compiling with djgpp gives a size of 56 (2 zero chars are added after
the first two).

If this is not a bug, how can I correct this?

Henno Vermeulen.