Re: [Boost-users] boost 1.47: gcc file dependency generation trips over BOOST_PARAMETER_MAX_ARITY

Subject: Re: [Boost-users] boost 1.47: gcc file dependency generation trips over BOOST_PARAMETER_MAX_ARITY
From: Ivan Le Lann (ivan.lelann_at_[hidden])
Date: 2011-09-15 08:02:00

----- "Ytsen de Boer" <yrdeboer_at_[hidden]> a écrit :

> Thank you for your answer.
>   I believe we are not on the same page.
>   Obviously, when I define the max arity to a value of 7 or more, the
> preprocessor will finish properly.
> 
>   But the point I am trying to make is more subtle, namely, that the
> generation of the project dependencies has not a thing to do with the
> boost max arity.

I think it does actually.
How could gcc track inclusions without preprocessing ?

#ifdef USE_LIB_A
#  include "a.h"
#else
#  include "b.h"
#endif

It seems very dangerous to me to use "-MMD" with different 
preprocessor definitions than at real compile time.
But I'm not an expert.
Anyway :

> 
>   I don't know what the boost max arity means or what its for, but it
> seems to me that it is a run time variable.

Have you checked that ?

My guess is that it is a compile time variable controlling
the number of template arguments for a particular class or function.
Pure compile time.

Regards,
Ivan