Issue 0252: incomplete argument types when calling non-prototyped functions

This issue has been automatically converted from the original issue lists and some formatting may not have been preserved.

Authors: Clive D.W. Feather <clive@demon.net>, UK C Panel
Date: 2001-09-07
Submitted against: C99
Status: Fixed
Fixed in: C99 TC3
Converted from: summary-c99.htm, dr_252.htm

Problem

Consider the code:

   void jim ();
    void sheila (void);
    // ...   sheila (jim ());   /* Line A */
    jim (sheila ());   /* Line B */

Line A violates the constraint of 6.5.2.2#2, that requires the argument to have a type that can be assigned to the parameter type. But line B doesn't because that constraint only applies to prototyped functions. 6.5.2.2#4 reads in part:

[#4] An argument may be an expression of any object type.

but this is not a constraint. Should it not be ? After all, the compiler has to know the type of the argument in order to compile the function call, so it can check at that point that the argument has a complete object type.

Suggested Technical Corrigendum

Add a new paragraph #1a following 6.5.2.2#1:

[#1a] Each argument shall have a type which is a completed object type.


Comment from WG14 on 2002-03-06:

Committee Response

This should not be a constraint.