[LLVMdev] Proposed: first class packed structures

[Chris Lattner]

On Fri, 8 Dec 2006, Andrew Lenharth wrote:
>> Here's an example of #1:
>>   extern struct { int x;  int y;  int z; } __attribute((packed)) foos;;
>> This should just be {int,int,int}, not <{int,int,int}>.
>
> no, consider
> struct foo { int x;  int y;  int z; } __attribute((packed));
> struct {char c; struct foo f;} bar;
>
> sizeof(bar) == 13
> if struct foo wasn't packed it's allignment would force a larger size for bar;

I would expect the type of bar to be:

<{sbyte, {int,int,int} }>

which has size = 13.

-Chris

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