Experimental Physics and
Industrial Control System

On 11/29/2017 12:43 PM, Dirk Zimoch wrote:
> The file anyscalar.h generates many warnings of the form
> 
> /afs/psi.ch/group/8431/dirk/git/BASE/epics-base-master/include/pv/anyscalar.h:98: warning: dereferencing pointer ‘<anonymous>’ does break strict-aliasing rules

The construct used (std::aligned_storage) is well defined in c++11.

http://en.cppreference.com/w/cpp/types/aligned_storage

> I am a bit concerned about that because it may lead to wrong optimization. I think this should either be fixed or -fno-strict-aliasing should be added to the compiler flags for recent gccs (i.e. not old vxWorks :-) )

GCC >=4.8.4 (at latest) doesn't warn about this even with -std=c++98.  So if anything, this is only need for older compilers.

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Re: warnings about strict aliasing Dirk Zimoch

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