Range of Enum Constants

[Karl Botts]

I am sending this to Microsoft; I thought it might be relevent here, too:

/*
Dear Microsoft Online,

	MSC 6.0 correctly compiles this:
*/

enum {
	A = (int)0x8001,
};

/*
	but rejects this:
*/
enum {
	B = (int)0x8000,
};
/*
	with:

enum.c
enum.c(16) : error C2141: value out of range for enum constant

	This doesn't make any sense, since both are valid values for a 
16-bit integer.

	This may be related to something I noticed in <limits.h>:

#define SHRT_MIN	(-32767)	/* minimum (signed) short value */
#define SHRT_MAX	  32767 	/* maximum (signed) short value */

	This is clearly wrong.  I don't have a copy of the ANSI standard, 
but I suppose it is possible that it requires that the the _MIN and _MAX 
constants for a signed integral type have the same absolute value.
If so we'll have to live with it, but otherwise you have a bad header 
file.

	If you have compiled the compiler using your <limits.h> this is
probably the source of the enum problem, above.  But I claim that 
regardless of the ANSI standard, the enum problem is a bug.
*/

/*
	You may wonder how I ran into this.  Well, I have a set of EMS 
access routines which generate error codes by clearing the al register 
if an EMS function fails; the native EMS error codes are in ah, and one
of them is 0x80.  I wanted to make a a set of enum constants for these 
codes.
*/