Clang scan-build output

[Maxim Dounin]

Hello!

On Wed, Nov 04, 2009 at 04:51:50PM -0800, Cliff Wells wrote:

> That's a pretty cool tool.  Surprising though that some really
> simplistic stuff generated false positives, e.g.:
> 
> "Value stored to 'qclass' is never read"
> 
>  qtype = (an->type_hi << 8) + an->type_lo;
>  qclass = (an->class_hi << 8) + an->class_lo;
>  len = (an->len_hi << 8) + an->len_lo;
>  ngx_log_debug3(NGX_LOG_DEBUG_CORE, r->log, 0,
> 	                  "resolver qt:%ui cl:%ui len:%uz", qtype, qclass, len);

Brian aparently analyzed build without debug, and ngx_log_debug3() 
resolves to nop there.  So it's not really false positive, but 
wrapping such cases into "#if (NGX_DEBUG)" just to make analyzer 
happy looks like overkill.

Maxim Dounin

> 
> Cliff
> 
> On Wed, 2009-11-04 at 14:59 -0800, Akins, Brian wrote:
> > Output from the clang static analyzer ( http://clang-analyzer.llvm.org/ )
> > for nginx-0.7.63
> > 
> > http://www.akins.org/scan-build-2009-11-04-1/index.html
> > 
> > 
> -- 
> http://www.google.com/search?q=vonage+sucks
> 
>