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Re: two objects in global scope have the same name

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Hello
Thanks a lot for comments.

"James Kuyper" <jameskuyper@verizon.net> wrote in message 
news:itid0a$i4g$1@dont-email.me...
> 6.9p5:
>> ... If an identifier declared with external
>> linkage is used in an expression (other than as part of the operand of a 
>> sizeof operator
>> whose result is an integer constant), somewhere in the entire program 
>> there shall be
>> exactly one external definition for the identifier; otherwise, there 
>> shall be no more than
>> one.
>
> Those "shall"s occur outside of a constraint section. Code which
> violates them therefore has undefined behavior (4p2). That means that
> the C standard imposes no requirements on what the implementation does
> with your code. In principle, that means that just about anything can
> happen.
>

Consider this snippet:

a.h:
extern int x;

a.c:
#include "a.h"
int x;

b.h:
extern long x(void);

b.c:
#include "b.h"
long x(void)
{
   return 1;
}

How does the Standard interpret this case?  I think that 6.9.1p6 applies to 
this case, and results in underfined behavior as well ?

Thanks. 

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two objects in global scope have the same name "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2011-06-17 12:32 -0400
  Re: two objects in global scope have the same name Shao Miller <sha0.miller@gmail.com> - 2011-06-17 13:08 -0500
  Re: two objects in global scope have the same name pete <pfiland@mindspring.com> - 2011-06-17 23:10 -0400
    Re: two objects in global scope have the same name Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-06-17 23:43 -0600
      Re: two objects in global scope have the same name James Kuyper <jameskuyper@verizon.net> - 2011-06-18 10:16 -0400
  Re: two objects in global scope have the same name China Blue Angels <chine.bleu@yahoo.com> - 2011-06-17 20:52 -0700
    Re: two objects in global scope have the same name "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2011-06-18 08:51 -0400
      Re: two objects in global scope have the same name James Kuyper <jameskuyper@verizon.net> - 2011-06-18 10:33 -0400
        Re: two objects in global scope have the same name "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2011-06-19 14:07 -0400
          Re: two objects in global scope have the same name James Kuyper <jameskuyper@verizon.net> - 2011-06-20 06:36 -0400
      Re: two objects in global scope have the same name China Blue Angels <chine.bleu@yahoo.com> - 2011-06-18 08:12 -0700

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