🚀 go-pugleaf

gstern@earth.usa.net (Greg Sternberg/PDS Inc) wrote:

> Peter van Klaveren (P.v.Klaveren@bcs.cs.philips.com) wrote:
> : enum
> : {
> :    CSEQ_IDLE,
> :    CSEQ_ERROR,
> :    CSEQ_ABORT,
> :    CSEQ_WAIT4RESPONSE
> : };
> 
> : int state = 3;
> 
> : if (state == CSEQ_WAIT4RESPONSE)
> : {
> :     // this code is not executed!!!
> :     ...
> : }
> 
>    You're making the assumption that the compiler is numbering your enums
>    sequentially from 0 - since the standard says nothing about how the
>    compiler could number your enums it could very well be using 0x1, 0x2, 
>    0x4, and 0x8.

From draft 7.2:

	The identifiers in an enumerator-list are declared as
	constants, and can  appear  wherever  constants  are  
	required.  If no enumerator-definitions with = appear, then
	the values of the corresponding constants begin at zero and
	increase by one as the enumerator-list is read from left to
	right.

The C standard (ISO 6.5.2.2) and ARM (7.2) also require this.


Michael M Rubenstein

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