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March 20th, 2013, 04:47 AM

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Bit fields

the foll code when run on gcc compiler gave 12 as output

Code:

struct aa{char a:3;int b:30;char c:3;}; printf("%d",sizeof(struct aa));

but since sizeof int is 4 and char is 1 then why does it give 12 instead of 8 as output????

March 20th, 2013, 06:44 AM

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it because of structure padding.
compiler use memory in the pack of 4 bytes.
thats why its giving u output as 12 byte.

to get 6 byte as output use

Code:

#pragma pack(1)

so compiler will not use structure padding.

March 20th, 2013, 10:07 AM

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Quote:

Originally Posted by eramit2010

to get 6 byte as output use

I think it should be 5 not six 4 for int and 1 for char

March 20th, 2013, 02:26 PM

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