Defect Report #010

Submission Date: 10 Dec 92
Submittor: WG14
Source: X3J11/90-044 (Michael S. Ball)
Question 1
typedef int table[]; /* line 1 */

table one = {1}; /*
line 2 */

table two = {1, 2}; /*
line 3 */

First, is the typedef to an incomplete type legal? I can't find a prohibition in the standard. But an incomplete type is completed by a later definition, such as line 2, so what is the status of line 3?
The type, of which table is only a synonym, can't be completed by line 2 if it is to be used in line 3. And what is sizeof(table)? What old C compilers seem to do is treat the typedef as some sort of textual equivalent, which is clearly wrong.
A typedef of an incomplete type is permitted.
Regarding objects one and two, refer to the standard subclause, page 24, lines 8-9: ``An array of unknown size is an incomplete type. It is completed, for an identifier of that type, by specifying the size in a later declaration ...'' [emphasis added]. The types of objects one and two are completed but the typ e table itself is never completed. Hence, sizeof(table) is not permitted.
An example very similar to that submitted is shown in example 6, subclause 6.5.7 on page 74, lines 16-23.
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