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From: Stephan Bergmann <stephan.bergmann@sun.com>
To: gcc-bugs@gcc.gnu.org
Subject: Aligning struct member has strange impact on struct alignment
Date: Wed, 14 Apr 2004 15:01:00 -0000	[thread overview]
Message-ID: <407D41E8.9000202@sun.com> (raw)

Hi all.

I have a strange effect with gcc 3.2.2 on Linux x86, where the C program

#include <stdio.h>
struct S1 { double m; };
struct S2 { double m __attribute__((aligned(4))); };
int main(void) {
     printf(
         "__alignof__(S1) = %d\n__alignof__(S2) = %d\n",
         __alignof__(struct S1), __alignof__(struct S2));
}

prints

__alignof__(S1) = 4
__alignof__(S2) = 8

Why is the alignment of S2 == 8 when I align its double member on 4?  Is 
that a bug, or am I missing something?

-Stephan


             reply	other threads:[~2004-04-14 13:51 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-04-14 15:01 Stephan Bergmann [this message]
2004-04-15 20:06 ` Jim Wilson

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