On 13 Jan, 2014, at 2:18 PM, Chris Jones <notifications@github.com> wrote:

> In CalibFormats/SiPixelObjects/src/PixelROCDACSettings.cc:
> 
> > @@ -482,7 +483,7 @@ int PixelROCDACSettings::read(std::istringstream& in, const PixelROCName& rocid)
> >      in >> tmp; CalDel_=tmp;
> >      in >> tag; 
> >      if (tag==k_DACName_WBC+":"){
> > -      static bool first=true;
> > +      static std::atomic<bool> first(true);
> >        if (first){
> 
> std::call_once requires a mutex
are you sure? I think it  is an implementation choice. Maybe we should move the discussion on using call_once elsewhere...

> and once TempRange_=4; is moved outside of that if this block of code will be functionally side effect free so there is no need for other threads to wait for it to complete.
and using LogWarning will make it thread safe anyway….
v.