Joe Buck - Re: -Wuninitialized issues (original) (raw)

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• From: Joe Buck
• To: Jeffrey A Law
• Cc: Diego Novillo , gcc at gcc dot gnu dot org,Mark Mitchell
• Date: Tue, 1 Nov 2005 10:32:20 -0800
• Subject: Re: -Wuninitialized issues
• References: 4365CA5E.3070401@codesourcery.com 1130802583.19967.122.camel@localhost.localdomain <200511011106.49922.dnovillo@redhat.com> <1130869072.19967.232.camel@localhost.localdomain>

On Tue, Nov 01, 2005 at 11:17:52AM -0700, Jeffrey A Law wrote:

On Tue, 2005-11-01 at 11:06 -0500, Diego Novillo wrote:

To prevent losing location information for the warning, I had modified the propagation engine to warn as it folded the expression away. Possibly a useful thing to have, but I don't think we want to put the burden of detecting uninitialized variables onto each optimizer :-)

Just an off-the-wall idea: What if dereferencing an uninitialized variable is considered a side effect? Then that side effect must be preserved unless it is unreachable. Consider

   while (i > 0)
      i--;
   // no more uses of i.

Instead of throwing everything away, this would become

__check_initialized(i);

and we would still get the warning.

• Follow-Ups:
  • Re: -Wuninitialized issues
    * From: Jeffrey A Law
• References:
  • Re: -Wuninitialized issues
    * From: Diego Novillo
  • Re: -Wuninitialized issues
    * From: Jeffrey A Law