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Re: enum bitfield


From: Eric Blake
Subject: Re: enum bitfield
Date: Thu, 22 Nov 2007 14:23:42 -0700
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According to Eric Blake on 11/22/2007 1:51 PM:
>>   input_type type : 8;
> 
>> The enum bitfield is a GNU extension.
> 
> Oh well.  I didn't want input_block to be any bigger than it has to be, so
> I'll just use a char instead, or perhaps something similar to how
> bool_bitfield in m4.h is defined according to GCC vs. C89.

Or more precisely, since C99 6.7.2.1 para 4 states:

A bit-field shall have a type that is a qualified or unqualified version
of _Bool, signed int, unsigned int, or some other implementation-defined type.

and since gnulib already states that _Bool is unsatisfactory due to the
limitations of the replacement <stdbool.h>, that leaves signed int and
unsigned int as the only two types safe for portable use in bitfields.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             address@hidden
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