Date: Sun, 4 Feb 1996 11:41:26 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Brad Burgan <bradtech AT i-link DOT net>
Cc: djgpp AT delorie DOT com
Subject: Re: __alignement__ in v2b5


On Fri, 2 Feb 1996, Brad Burgan wrote:

> struct TestStruct
>   {
>   char var1;
>   short var2  __attribute__ ((packed));
>   };
> 
> int main(void)
>   {
>   printf("sizeof(TestStruct): %i", sizeof(TestStruct));
>   }
> // ===end of file===
> 
> Can anyone tell me why this program produces:
> 
> sizeof(TestStruct): 4

You called this test.cpp, so I assume you've compiled it as a C++ 
program.  First, you should declare all the struct fileds as packed.  But 
the *real* bad news is that in GCC 2.7.2 there is a bug in the C++ 
compiler which makes the packed structs not packed (they work ok in C 
programs).

> Info says you can do this:
> 
> struct S
>   {
>   blah
>   } __attribute__ ((packed));  // <<<<< line 106
> 
> But I get a compiler error that ; is missing on line 106

Did you put a ; after `blah'?  If not, that is the error.
You can also use the -fpack-struct option (new with gcc 2.7) to make all 
the structs packed.