Something about std::list<> member functions.

[Jerry Quinn]

Gabriel Dos Reis writes:
 > Jerry Quinn <jlquinn@optonline.net> writes:
 > 
 > | Gabriel Dos Reis writes:
 > |  > Nathan Myers <ncm-nospam@cantrip.org> writes:
 > |  > 
 > |  > | On Sat, Aug 09, 2003 at 08:55:16PM +0200, Gabriel Dos Reis wrote:
 > |  > | > Dhruv Matani <dhruvbird@gmx.net> writes:
 > |  > | > 
 > |  > | > [...]
 > |  > | > 
 > |  > | > | form At&T syntax, but I thought (and still do think) that compiler
 > |  > | > | technology should have evolved by now so as to optimize such stuff into
 > |  > | > | nothingness...... And, looking at g++ optimizations, I definitely
 > |  > | > | thought that it could (at least now) optimize away the layer.
 > |  > | > 
 > |  > | > See recent discussions on gcc@gcc.gnu.org about inlining.
 > |  > | 
 > |  > | Without consulting those, I recall Jason Merrill mentioning that
 > |  > | you can get enormous optimization improvements just from declaring
 > |  > | the inline functions' arguments "const", unnecessarily.  Is that 
 > |  > | advice still current?  Since it doesn't affect the ABI or standard 
 > |  > | conformance, that seems worth doing where it makes a difference.
 > |  > 
 > |  > We already pass the arguments by const reference.
 > | 
 > | If I remember right, the issue isn't passing by const ref.
 > 
 > Here is what I meant:
 > 
 >    struct less {
 >       template<class T>
 >        bool operator()(const T& a, const T& b) const
 >        { return a < b; }
 >    };
 > 
 > the arguments are passed by const reference.  Is that different fro
 > what you intend below?  If yes, please elaborate because I can't see
 > the difference. 

Yes.  What you've written should be sufficient, but apparently there's
a front-end deficiency that may need:

struct less {
    template<class T>
     bool operator()(const T& const a, const T& const b ) const
     { return a < b; }
};

Note the extra const's on a and b.  I don't remember the gory details
on why this was needed, though.

*checks inbox*

This message is what I recall about the issue:

http://gcc.gnu.org/ml/libstdc++/2003-02/msg00302.html

Jerry