Why windows g++ doesn't find external header files

Question

My filename : firstnana.cpp

Current Folder : D:\projects\cpp\guinana

My headers :

#include <nana/gui.hpp>
#include <nana/gui/widgets/label.hpp>
#include <nana/gui/widgets/button.hpp>

Compiling :

g++ firstnana.cpp -I./nana/include/nana

Example : The <nana/gui.hpp> is located in D:\projects\cpp\guinana\nana\include\nana\gui.hpp

The output Error : firstnana.cpp:1:24: fatal error: nana/gui.hpp: No such file or directory compilation terminated.

Answer 1

you already have "nana" directory in your -I parameter. Don't repeat it in the includes.

#include <gui.hpp>
#include <gui/widgets/label.hpp>
#include <gui/widgets/button.hpp>