RE: using typedef to create aligned types
Andrew Grant <[email protected]> Wed, 1 Dec 2004 23:53:03 -0000
| Newsgroups | gmane.games.devel.windows |
|---|---|
| Message-ID | <56C9B4CE640B7044AAF74431F9C963E104ED7635@tankard.brighton.climax.co.uk> |
You're changing the alignment, not the size. Alignment determines where a variable will be allocated in memory, e.g FredAligned16 will always be allocated on a 16 byte memory boundry but the size of both types will be the same. A. > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On > Behalf Of Andras Balogh > Sent: Wednesday, December 01, 2004 3:46 PM > To: [email protected] > Subject: [GD-Windows] using typedef to create aligned types > > MSDN says that I can use typedef to make aligned versions of > my types, eg: > > typedef __declspec(align(16)) Fred FredAligned16; > > This works when I declare variables, eg: > > Fred fred1; > FredAligned16 fred2; > > fred2 is 16 bytes aligned, while fred1 is not > > But the strange thing is that sizeof(Fred) == > sizeof(FredAligned16) is true, even though Fred's size is not > a multiple of 16 bytes... > > When I declare different types (ie. not using typedef), then > the sizeof will be different because the aligned type will be > padded to the next multiple of > 16 bytes. > > Is this a bug in the compiler?? > > > > Thanks, > > Andras > > > > > ------------------------------------------------------- > SF email is sponsored by - The IT Product Guide Read honest & > candid reviews on hundreds of IT Products from real users. > Discover which products truly live up to the hype. Start reading now. > http://productguide.itmanagersjournal.com/ > _______________________________________________ > Gamedevlists-windows mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/gamedevlists-windows > Archives: > http://sourceforge.net/mailarchive/forum.php?forum_id=555 > ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/ _______________________________________________ Gamedevlists-windows mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/gamedevlists-windows Archives: http://sourceforge.net/mailarchive/forum.php?forum_id=555