Re: [boost] [algorithm][hex] function hex_char_to_int in unnamed namespace in header file

Subject: Re: [boost] [algorithm][hex] function hex_char_to_int in unnamed namespace in header file
From: Marshall Clow (mclow.lists_at_[hidden])
Date: 2012-12-03 12:24:56

On Nov 27, 2012, at 11:53 AM, Felipe Magno de Almeida <felipe.m.almeida_at_[hidden]> wrote:

> On Tue, Nov 27, 2012 at 5:41 PM, Marshall Clow <mclow.lists_at_[hidden]> wrote:
>> On Nov 27, 2012, at 9:55 AM, Felipe Magno de Almeida <felipe.m.almeida_at_[hidden]> wrote:
>> 
>>> Hello,
>>> 
>>> AFAIK, unnamed namespaces are dangerous in headers. There is a
>>> commentary just above the function definition:
>>> 
>>> // this needs to be in an un-named namespace because it is not a template
>>> // and might get included in several compilation units. This could cause
>>> // multiple definition errors at link time.
>>> 
>>> But it seems the better thing would be to define it inline. It is
>>> exactly because it can be used in several
>>> translation units that it can cause an ODR violation if defined
>>> in a unnamed namespace AFAIK.
>> 
>> I have no problem with declaring it inline, but that's just a suggestion.
>> The compiler is completely free to generate code for it out-of-line.
> 
> I didn't meant I want the function to be inlined by the compiler. What I mean
> is that putting it in a unnamed namespace causes undefined behavior(AFAIK).

I don't believe that's true, but I'm willing to be convinced.

-- Marshall

Marshall Clow     Idio Software   <mailto:mclow.lists_at_[hidden]>

A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait).
        -- Yu Suzuki