Re: [RFC] net/hsr: Add support for IEC 62439-3 High-availability Seamless Redundancy

David Miller wrote:

From: Stephen Hemminger <redacted>
Date: Wed, 4 Apr 2012 16:55:59 -0700

quoted

That isn't so bad, doing a memcpy versus a structure copy.

GCC is going to inline the memcpy and thus we'll still do the
unaligned accesses.  This change therefore won't fix the problem.

Well, it does work for me, with gcc-4.2.2-compiled linux-2.6.37 running
on an AVR32 board.

Just out of curiosity, what's the mechanism behind this inline
assignment that turns the memcpy into an unaligned access? If gcc is 
"smart" enough to detect a bunch of char * accesses and turn them 
into unaligned 32-bit accesses, isn't that a bug in gcc?

Or will this only happen on archs which __HAVE_ARCH_MEMCPY? (But looking
at a couple of arch/xxx/lib/string.c, these too seem to take alignment
into account.)

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