|OK, putting wrong option may be one of the issues.
I did put BOTH --cflag and --libs in complier and linker options. I also tried
this combined syntax
`pkg-config --cflags --libs gtk+-3.0`
The compiler and linker verbose outputs looks OK ( too big to repost here ) , BUT the unresolved error is apparently different issue.
I am enclosing what I posted in Eclipse forum here:
This error has been posted years ago and there was NO SOLUTION,
See this old post
[b]However, this only solved the issue of adding all the header files manually. Now I encounter errors like "Function 'G_CALLBACK' could not be resolved". I tried to compile my source-code (the first example of the GTK3 tutorial) in a terminal using the simple "gcc `pkg-config --cflags gtk+-3.0` -o example-0 First_GTK_test.cpp `pkg-config --libs gtk+-3.0`" command and it works. So the issue must be an Eclipse setting issue.[/b]
Every GTK tutorial is same - download / install GTK and run sample code in your editor...
It is up to the user to figure out how to option complier / linker to "include sources and link libraries"
Adding `pkg-config --cflags --libs gtk+-3.0` should work, I get expected verbose output , but it does not.
Even after that is done the compilation will fail because #include <gtk gtk.h=""> is unresolved.
Here is an output of whereis
z@z-desktop $ whereis gtk.h
Any help woudl be appreciated
End of Eclipse post.
I am really at lost where the reference
<gtk gtk.h=""> came from and unsure how to find gtk.h manually - where ?
Appreciate all the help with such trivial issue.