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Re: Is this expected gcc behaviour?

On Fri, Aug 06, 2004 at 11:08:08AM -0700, Aaron J. Grier wrote:

> if newer versions of gcc are optimizing this out (and according to C
> standard that's OK), how else can this be accomplished?

The version of gcc I'm using (3.3) doesn't optimize away the
test of an external objects address, so I can't test this, but
how about:


extern unsigned char v;  // address of v is defined at link time

void foo(void)
{
  volatile unsigned long u = (unsigned long)&v;
  if (u)
    bar();  
}

-- 
Grant Edwards
grante@visi.com

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