Issue 0034.02: If so, can one then write conflicting declarations in disjoint scopes?

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

Authors: Stephen D. Clamage, WG14
Date: 1992-12-10
Reference document: X3J11/91-038
Submitted against: C90
Status: Closed
Converted from: dr.htm, dr_034.html

If no size information is known in the outer scope, then consider the following example:

extern int a[];
 int f() {
 extern int a[10];
 ...
 }
 int g() {
 extern int a[20]; /* error? */
 ...
 }

Is this legal? If not, does it violate a constraint?

Comment from WG14 on 1997-09-23:

Response

The example exhibits undefined behavior. It does not violate a constraint. Subclause 6.1.2.2, page 21, lines 10-13 describe “same object;” subclause 6.1.2.6, page 25, lines 9-10 require that “All declarations that refer to the same object or function shall have compatible type; otherwise, the behavior is undefined.”