Should _GLIBCXX_DEBUG affect tr1/array?

Jonathan Wakely jwakely.gcc@gmail.com
Mon Jan 16 14:27:00 GMT 2012


On 16 January 2012 14:24, Jonathan Wakely wrote:
> On 16 January 2012 12:28, Edward Rosten wrote:
>>
>> I've been reading through some of the libstdc++ headers to try to
>> determine the correct way to do this.
>>
>> it like a good way might be to have:
>>
>> #ifdef _GLIBCXX_DEBUG
>> #  include<debug/macros.h>
>> #endif
>>
>> Then, operator[] would become:
>>     // Element access.
>>     reference
>>     operator[](size_type __n)
>>     {
>>        #ifdef _GLIBCXX_DEBUG
>>          __glibcxx_check_subscript(__n);
>>        #endif
>>        return _M_instance[__n];
>>     }
>
> That's not a valid constexpr function.

Also, the right way to have used that macro would be:

#include <debug/debug.h>

     // Element access.
     reference
     operator[](size_type __n)
     {
        __glibcxx_requires_subscript(__n);
        return _M_instance[__n];
     }

When not in debug mode that macro expands to nothing.



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