well i do not know what is excactly the answer to the question of the compiler. If you want to help me out and tell me where do i see that i can tell you. I do not want to answer anything i do not know. I did the procedures of the sites about using the eclipse with arduino with avr plugin etc.There are 2 fixed projects that work on the sites the first for arduino core and the other for a blink project that i use to make new projects. I have added some other lib folder to store my own lib. So i do now know what is the answer in witch is the compiler. There is also a problem with null that it does not understand.
Well also in project -->properties --> C/C++ builder --> there is avr assempler ,avr compiler c/c++, avr linker (which i think the last has the problem cause when i open eclipse and build all withoutdoing anything else i get no errors, but when i try to open the .cpp files of the libraries then the problems and the error starts then i get error.)
also inside project-->properties--->Builder i get : CDT builder and Scanner Configuration builder