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From: vasta@apollo.HP.COM (John Vasta)
Newsgroups: comp.sys.apollo
Subject: Re: GCC bug?
Message-ID: <4cc0203b.20b6d@apollo.HP.COM>
Date: 11 Sep 90 20:32:00 GMT
References: <1990Sep10.151351.20186@water.waterloo.edu> <1990Sep11.125319.21412@ncsuvx.ncsu.edu>
Sender: root@apollo.HP.COM
Reply-To: vasta@apollo.HP.COM (John Vasta)
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Organization: Hewlett-Packard Company, Apollo Division; Chelmsford, MA
Lines: 30

In article <1990Sep11.125319.21412@ncsuvx.ncsu.edu> jwb@cepmax.ncsu.edu writes:
>I'm using gcc version 1.37.1 (with John Vasta's patches) to compile
>the following program on a DN4500 (SR10.2, BSD4.3):
>
>     1	main()
>     2	{
>     3	  char x[10];
>     4	  long i;
>     5	
>     6	  for (i = 0; i <= 10; i++) x[i] = 'a';
>     7	
>     8	  return 0;
>     9	}
>
>Upon executing the program I get:
>
>% a.out
>unable to unwind stack because of invalid stack frame (process
>manager/process fault manager)
>
>However, if I swap lines 3 and 4 it runs perfectly.  Any ideas?

A classic pitfall - you're writing beyond the end of the array.
Legal index values for a 10-element array range from 0 to 9, but
you're writing to x[10].

John Vasta                Hewlett-Packard Apollo Systems Division
vasta@apollo.hp.com       M.S. CHR-03-DW
(508) 256-6600 x5978      300 Apollo Drive, Chelmsford, MA 01824
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