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Re: [PATCH] Remove check for undefined behaviour

 

Well, as for removing them being a good or bad idea - the compiler is
probably doing that anyway. I just tested on GCC, at -O1 or greater it
just assumes all references are non-NULL and replaces any "&ref != 0"
with a hard-coded boolean 'true'. So... there's a pretty good chance we
haven't had those checks for quite some time.

On Wed, Sep 28, 2016 at 09:24:40AM -0400, Wayne Stambaugh wrote:
> I normally don't like to rant but OMFG!  I just looked at the code path
> that lead to this wonderful piece of code and I'm now regretting that.
> You just cannot unsee that.  See if you can follow the logic (assuming
> logic was actually used to write this code) backwards from
> Triangle::NeighborAcross().  I'm not sure removing the invalid null
> reference checks is a good idea even though I've seen the compiler
> complain about it and agree with it.  In what universe do you blindly
> convert a potentially NULL pointer into a C++ reference, pass it to the
> caller, and go merrily on you way?  This really needs to be rewritten
> using pointers with the appropriate NULL pointer checks along the way.
> It's hard to imagine this ever worked properly.
> 
> On 9/27/2016 1:33 PM, Simon Richter wrote:
> > 
> > Triangle::NeighborAcross returns a reference, which must refer to a valid
> > object whose address cannot be 0. Thus, this test is nonsensical.
> > ---
> >  polygon/poly2tri/sweep/sweep.cc | 16 ----------------
> >  1 file changed, 16 deletions(-)
> > 
> > 
> > 
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