From: Chris Lattner <sabre@nondot.org>
To: gcc-help@gcc.gnu.org
Subject: attribute aligned(4) ignored
Date: Tue, 26 Jul 2005 01:04:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.61.0507252003000.10523@nondot.org> (raw)
Hi All, I'm trying to reduce the alignment of the double in this structure
to 4 bytes (from 8) on Darwin. The goal of doing this is to reduce the
structure to 12 bytes in size. Here is my testcase:
struct Test {
double D __attribute__((aligned(4))); // only 4 bytes, not 8!
int X;
};
int X() {
return sizeof(struct Test); // Should return 12, not 16.
}
Despite my attempt above, the structure is still 16 bytes in size, due to
the tail padding required to pad the structure to ensure 8-byte alignment.
Does anyone know how to reduce the alignment of the double, eliminating
the tail padding?
Thanks,
-Chris
--
http://nondot.org/sabre/
http://llvm.org/
next reply other threads:[~2005-07-26 1:04 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-07-26 1:04 Chris Lattner [this message]
2005-07-26 3:22 ` Ian Lance Taylor
2005-07-26 4:58 ` Chris Lattner
2005-07-26 5:02 ` corey taylor
2005-07-26 5:04 ` Chris Lattner
2005-07-26 5:25 ` Ian Lance Taylor
2005-07-26 5:57 ` Chris Lattner
2005-07-26 6:27 ` Ian Lance Taylor
2005-07-26 6:44 ` Chris Lattner
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