Re: PATCH: fix occasional warning

[Peter Stephenson <pws@xxxxxxx>]

On Mon, 06 Jun 2011 12:32:55 +0100, Vincent Lefevre <vincent@xxxxxxxxxx>  
wrote:
> On 2011-06-06 10:03:58 +0100, Peter Stephenson wrote:
> > The code here is actually safe, but some (now old) versions of gcc
> > produce a warning anyway.  Better to rely on more recent versions
> > optimising out the unused value.
>
> But recent or future GCC versions may warn against values set but
> unused.

The code is of this form:

  uint16 value = 0; /* this is strictly unnecessary */
  uint16 value_set = 0;

  if (some_test)
  {
     value = some_value;
     value_set = 1;
  }
  /* ... */
  if (value_set)
  {
     do_something_with(value):
  }

If compilers start warning about unused initialisation to
value in a case like this, I for one will get very cross.
It is having no other effect than making it hard for you
to write safe, portable code.

pws


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