Re: how to pack bitfields and make it cross container boundry

Just a guess-- have you tried a char pack: 6 afterwards? It may be that,
given the luxury of using 16 bits anyway, the compiler decides to put b onto
a byte boundary, but if you use up all 16 bits, it will squeeze b closer to
a.

Worth a try I'd have thought.

S.

"Lokicer" <lokicer@xxxxxxx> wrote in message
news:OL2ZLAzTGHA.4080@xxxxxxxxxxxxxxxxxxxxxxx
hi,
i build a bitfield structure and pack it as following

#pragma pack(1)
typedef struct
{
char a:5;
char b:5;
} test_t;
#pragma pack()

i want b follows a closely and try it in vc++6, but there is 3 bits space
between a and b.

how to make bitfield corss byte boundry?

thanks in advance

Lokicer



.

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