Q67037: Embedded Unnamed Structures and Unions Cannot Be Initialized

Article: Q67037
Product(s): See article
Version(s): 6.00 6.00a | 6.00 6.00a
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | buglist6.00 buglist6.00a | mspl13_c
Last Modified: 20-NOV-1990

The ability to utilize "nameless" structures and unions provides a
convenient shorthand for referring to structures embedded in other
structures, but the current design of the compiler does not allow
these unnamed members to be initialized.

Permitting initialization involves a number of ambiguities that the
compiler does not currently track. If you attempt to initialize a
nameless structure or union, the compiler will generate a "C2097 :
illegal initialization" error. The sample code below demonstrates this
limitation.

Microsoft has confirmed this to be a problem in C versions 6.00 and
6.00a and QuickC versions 2.50 and 2.51. We are researching this
problem and will post new information here as it becomes available.

Sample Code
-----------

typedef struct _reg {
    union {
        long   eax;
        short  ax;
        };
    union {
        long   ebx;
        short  bx;
        };
    } regtype;

regtype  foo = { {1l}, {2l} };    /* This initialization attempt
                                     generates a C2097 error     */

void main(void)
{
}

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