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Re: header only C++ code or not?

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On Thu, 07 Jul 2011 11:40:22 -0400
Garrett Hartshaw <ghartshaw@gmail.com> wrote:

> On Thu, 7 Jul 2011 14:57:44 +0200, "Balog Pal" <pasa@lib.hu> wrote:
> > "Thomas Boell" <tboell@domain.invalid> 
> > > 
> > > In addition to what others said, putting implementation in header 
> files
> > > can give the compiler better chances for optimization and 
> inlining. If
> > > the implementation is in a separate compilation unit, the compiler
> > > can't inline because it doesn't know the function body.
> 
> 
> > Nothing enforces the classic "dumb linker" model.
> 
> Newer gcc versions have the -flto option for this purpose. I don't 
> know about other compilers.

Nice. I didn't know about GIMPLE and the -flto flag.

It seems to be rather new (released in May 2010 with gcc 4.5
apparently). If it's true that code using LTO is effectively compiled
twice [1], then that could be a reason why one would not want to use it.

[1] http://lwn.net/Articles/387447/

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Thread

header only C++ code or not? kathy <yqin_99@yahoo.com> - 2011-07-06 14:27 -0700
  Re: header only C++ code or not? "Andrew Holme" <ah@nospam.com> - 2011-07-06 22:42 +0100
    Re: header only C++ code or not? "Bo Persson" <bop@gmb.dk> - 2011-07-07 19:17 +0200
  Re: header only C++ code or not? Sam <sam@email-scan.com> - 2011-07-06 17:23 -0500
  Re: header only C++ code or not? Noah Roberts <roberts.noah@gmail.com> - 2011-07-06 16:14 -0700
    Re: header only C++ code or not? "MikeP" <mp011011@some.org> - 2011-07-07 15:35 -0500
    Re: header only C++ code or not? "MikeP" <mp011011@some.org> - 2011-07-07 15:45 -0500
  Re: header only C++ code or not? "Paul" <pchristor@yahoo.co.uk> - 2011-07-07 01:24 +0100
  Re: header only C++ code or not? Thomas Boell <tboell@domain.invalid> - 2011-07-07 14:24 +0200
    Re: header only C++ code or not? "Balog Pal" <pasa@lib.hu> - 2011-07-07 14:57 +0200
      Re: header only C++ code or not? Garrett Hartshaw <ghartshaw@gmail.com> - 2011-07-07 11:40 -0400
        Re: header only C++ code or not? Thomas Boell <tboell@domain.invalid> - 2011-07-07 19:38 +0200
          Re: header only C++ code or not? Garrett Hartshaw <ghartshaw@gmail.com> - 2011-07-09 09:06 -0400
            Re: header only C++ code or not? Thomas Boell <tboell@domain.invalid> - 2011-07-09 16:23 +0200
    Re: header only C++ code or not? "Bo Persson" <bop@gmb.dk> - 2011-07-07 19:16 +0200

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