order of headers lookup

order of headers lookup

[Dima Sorkin]

Hi.
 This feature of gcc seems strange to me:

Consider a directory structure of a tiny project:
/main.cpp (#include "foo.hpp" )
/d1/bar.hpp
/d2/foo.hpp (#include "bar.hpp")
/d2/bar.hpp

then compiling
 > g++ -I d1 -I d2 main.cpp -o main
will include /d2/bar.hpp instead of /d1/bar.hpp as I expected
( I expected so because "d1/" is listed first in "-I" options).

Such a behaviour of g++ limits the use of "sandboxes" in c++
projects ( consider the /d1/ directory as a sandbox of a real project).

Hope I don't miss something.

Thank you.
 Dima.

Re: order of headers lookup

[Eljay Love-Jensen]

Hi Dima,

#include "" checks current directory first.

Use #include "d1/bar.hpp" in your foo.hpp.

HTH,
--Eljay

Re: order of headers lookup

[Dima Sorkin]

Quoting Arturas Moskvinas :
> > directory structure of a tiny project:
> > /main.cpp (#include "foo.hpp" )
> > /d1/bar.hpp
> > /d2/foo.hpp (#include "bar.hpp")
> > /d2/bar.hpp
> > 
> > then compiling
> >  > g++ -I d1 -I d2 main.cpp -o main
> > will include /d2/bar.hpp instead of /d1/bar.hpp as I expected
> > ( I expected so because "d1/" is listed first in "-I" options).
> 
> It is from C preprocessor manual:
> #include "file"
>     This variant is used for header files of your own program. It
> searches for a file named file first in the directory containing the
> current file, then in the same directories used for <file>.
> 
> So, i think you should use #include <bar.hpp> to get your wanted behavior...

Yes, it works.
  Thank you.
 Dima.