Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!wums2!tan_j
From: tan_j@wums2.wustl.edu
Newsgroups: comp.sys.sgi
Subject: Re: Another C compiler bug
Message-ID: <3734.26a442ed@wums2.wustl.edu>
Date: 18 Jul 90 16:07:24 GMT
Lines: 28


Alright, this is actually in addition to my comments about the C code.
I was saying that it is easily it is easy to forget the initialization
of pointer, and I prove it myself.  I forgot to indicate that the
ap->slot itself must be initialized.  Therefore, add something like,
      int a;    
      ap->slot = (void *)&a;  
somewhere along the line is a must.

Another flaw that I did not see is
the register declaration.  register storage class only takes word size 
variable.  So, the declaration
      register struct anystruct  *pointer_variable;
is OK because pointer is essentially a word-size variable. But
      register struct anystruct plain_variable;
is a piece of bad code !   If anystruct is declared as
      struct anystruct {
      	int	a;
      	char 	b[50];
        void	*c;
      };
Then it is obvious that a register cannot hold all variables declared in
the structure.  Although in your case, you declared a struct with only
a void pointer member.  I don't really know the answer.  I guess it
depends on the compiler ?  Comments welcome.

"Never do it on early morning"
tan_j@wums.wustl.edu