Help with bit-field semantics in C and C++

[Gabriel Dos Reis]

Mike Stump <mrs@apple.com> writes:

| On Tuesday, August 24, 2004, at 04:20  PM, Gabriel Dos Reis wrote:
| > for which the minimum bits of representation is 1, 7 is not an
| > enumeration value.  A fortiori, it is not a honest unspecified
| > enumeration value.
| 
| The honest qualifier doesn't appear in my definition of the C++
| language; it only has specified and unspecified values.

It was taken from your message I was replying to.

| 
| Another way to think about this is to examine:
| 
| #include <stdio.h>
| #include <string.h>
| 
| enum E { foo = 3 } e;
| 
| int
| main() {
|    memset (&e, ~(unsigned char)0, sizeof (e));
|    printf ("%u\n", (unsigned int)e);
| }
| 
| The above program violates no rules of C++.  The value printed is
| either specified, or unspecified.  Which do you think it is, and if
| specified, which value is printed?

you forgot the option implementation-defined, which actually is the
case here.

-- Gaby