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Re: extern array as a pointer

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> > why does the following program crash at line# 20.
> > Is it even legal to define array as an integer
> > pointer while infact it's original definition is
> > single dimensional array or five elements.
> >
> >  1 #include "stdio.h"
> >   2
> >   3 int foo();
> >   4
> >   5 int array[5];
> >   6
> >   7 int main()
> >   8 {
> >   9    foo();
> >  10    printf("array[0] is %u", array[0]);
> >  11    return(0);
> >  12 }
> >  13
> >  14 foo.c:
> >  15
> >  16 extern int *array;
> >  17
> >  18 int foo()
> >  19 {
> >  20   arr[0]= 10;  
> 
> Did you mean array[0] here?
> 
> >  21   return(0);
> >  22 }
> >
> >  
> 
> You have a normal array in one module which is defined as a pointer
> to array in another, assuming arr was meant to be array. Try writing:
> 
> extern int array[];
> 
> in foo.c

But why? Why is "extern int *array" containing the first element which
is 0? Why doesn't the compiler or rather the linker warn about this? Is
the type information lost for the linker?

In the past i used *array and array[] interchangeable. I might have to
reconsider that.

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extern array as a pointer sinbad <sinbad.sinbad@gmail.com> - 2016-07-12 03:06 -0700
  Re: extern array as a pointer BartC <bc@freeuk.com> - 2016-07-12 11:45 +0100
    Re: extern array as a pointer Frank Tetzel <s1445051@mail.zih.tu-dresden.de> - 2016-07-12 13:58 +0200
      Re: extern array as a pointer Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-07-12 13:33 +0100
      Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:30 -0700
        Re: extern array as a pointer James Kuyper <jameskuyper@verizon.net> - 2016-07-12 12:52 -0400
          Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 11:30 -0700
            Re: extern array as a pointer supercat@casperkitty.com - 2016-07-12 11:51 -0700
        Re: extern array as a pointer supercat@casperkitty.com - 2016-07-12 10:55 -0700
    Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:28 -0700
  Re: extern array as a pointer Nobody <nobody@nowhere.invalid> - 2016-07-12 13:26 +0100
    Re: extern array as a pointer Keith Thompson <kst-u@mib.org> - 2016-07-12 09:26 -0700
  Re: extern array as a pointer Richard Heathfield <rjh@cpax.org.uk> - 2016-07-12 13:46 +0100
  Re: extern array as a pointer James Kuyper <jameskuyper@verizon.net> - 2016-07-12 12:33 -0400

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