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From: schmidt@glacier.ics.uci.edu (Doug Schmidt)
Newsgroups: gnu.g++.bug
Subject: Re: G++ 1.36 problem?
Message-ID: <1989Oct16.222036.20829@paris.ics.uci.edu>
Date: 16 Oct 89 22:20:36 GMT
References: <46991@bbn.COM>
Sender: news@paris.ics.uci.edu (Network News)
Reply-To: schmidt@glacier.ics.uci.edu (Doug Schmidt)
Organization: University of California, Irvine - Dept of ICS
Lines: 31
In-reply-to: mthome@bbn.com (Mike Thome)

In article <46991@bbn.COM>, mthome@bbn (Mike Thome) writes:
>Now that I've got g++ working here (thanks those who responded to my
>earlier plea for help), I've got another problem...
>The following code fragment (from InterViews):
>  class Resource {
>  public:
>      Resource () { refcount = 1; }
>      ~Resource () { if (--refcount > 0) { this = 0; } }
>  
>      void Reference () { ++refcount; }
>      int LastRef () { return refcount == 1; }
>  private:
>      unsigned refcount;
>  };
>
>Generates the following error message:
>  foo.c: In method Resource::~Resource ():
>  foo.c:4: assignment of read-only parameter `$this'
>
>As far as I can tell from Stroustrup, this appears to be a perfectly
>valid use of THIS in a destructer.  What's going on here?

Assigning to this is an anachronism.  However, you can make g++
accept this via the -fthis-is-variable option.

Doug
--
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