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[mistake] chapter 9.7 - char at the end of the struct is also size aligned #352

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[mistake] chapter 9.7 - char at the end of the struct is also size aligned #352

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2 changes: 1 addition & 1 deletion content/english/hpc/cpu-cache/alignment.md
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Expand Up @@ -55,7 +55,7 @@ struct Data {
};
```

When stored succinctly, this structure needs a total of $1 + 2 + 4 + 1 = 8$ bytes per instance, but even assuming that the whole structure has the alignment of 4 bytes (its largest member, `int`), only `a` will be fine, while `b`, `c` and `d` are not size-aligned and potentially cross a cache line boundary.
When stored succinctly, this structure needs a total of $1 + 2 + 4 + 1 = 8$ bytes per instance, but even assuming that the whole structure has the alignment of 4 bytes (its largest member, `int`), only `a` and `d` will be fine, while `b` and `c` are not size-aligned and potentially cross a cache line boundary.

To fix this, the compiler inserts some unnamed members so that each next member gets the right minimum alignment:

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