warning: dereferencing type-punned pointer will break strict-aliasing rules

[Nathan Sidwell]

Brian Dessent wrote:
> Jeffrey Holle wrote:
> 
>> On release builds, wxWidgets code emits a lot of these warnings:
>>    warning: dereferencing type-punned pointer will break strict-aliasing
>> rules
>>
>> Questions:
>>
>>    1.  Are these warnings benign?  If so can they be suppressed?
>>    2.  If not, what level of optimization should I regress to avoid these
>> warnings?
> 
> I would certainly not ignore them.  They indicate that the code being
> compiled probably violates the ISO C standard rules for type aliasing,

which _may_ break the aliasing rules.

If you examine the code being warned about, and find it benign, you may insert 
an intermediate void * cast to silence the warning.

nathan

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