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Date: Sat, 07 Sep 2013 21:37:00 -0000
From: Marc Glisse <marc.glisse@inria.fr>
To: Mike Stump <mikestump@comcast.net>
cc: "gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
Subject: Re: operator new returns nonzero
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On Sat, 7 Sep 2013, Marc Glisse wrote:

> On Sat, 7 Sep 2013, Mike Stump wrote:
>
>> Can this throw:
>> 
>> void *operator new (long unsigned int s) {
>>  return 0;
>> }
>> 
>> ?  Is this allowed to return 0?
>
> I think using this function is illegal. It isn't marked noexcept, so it isn't 
> allowed to return 0.

And if I compile your code with gcc, I get nice warnings (though I get 
them twice and the column number is not so good):

m.cc: In function 'void* operator new(long unsigned int)':
m.cc:2:12: warning: 'operator new' must not return NULL unless it is 
declared 'throw()' (or -fcheck-new is in effect) [enabled by default]
      return 0;
             ^
m.cc: At global scope:
m.cc:1:7: warning: unused parameter 's' [-Wunused-parameter]
  void *operator new (long unsigned int s) {
        ^


-- 
Marc Glisse