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Re: gcc-4.5/4.4: Bug in .subreg1 pass?

On 02/24/2011 06:04 PM, Michael Matz wrote: 
Funny.  As far back as I remember we consistently said that bits of the
same word, but outside the subreg are left with undefined values after
storing into the subreg, except if wrapped with a strict_low_part.  In
fact that's the whole point of strict_low_part.  I'm pretty sure we assume
this documented semantics in various parts of the compiler.

You both are correct. AVR has

/* Width of a word, in units (bytes).  */
#define UNITS_PER_WORD 1

Paolo

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