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Re: [power-gnu-discuss] -te500v2 and packed attribute
- To: "S. Couture & K. Musgrove" <muscou@xxxxxxxxxxxx>
- Subject: Re: [power-gnu-discuss] -te500v2 and packed attribute
- From: Mark Mitchell <mark@xxxxxxxxxxxxxxxx>
- Date: Wed, 07 May 2008 16:37:41 -0700
S. Couture & K. Musgrove wrote:
This seem to be a bug, the code generated is byte access only.
# cat test.c
struct a_packed{
int data;
} __attribute__((packed));
struct a_unpacked{
int data;
};
void test_packed(int in)
{ struct a_packed * ptr;
ptr->data = in;
}
void test_unpacked(int in)
{ struct a_unpacked * ptr;
ptr->data = in;
}
The compiler cannot assume anything about alignment of a packed
structure and therefore cannot assume that "ptr->data" as at a
byte-aligned address.
--
Mark Mitchell
CodeSourcery
mark@xxxxxxxxxxxxxxxx
(650) 331-3385 x713
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