Well, I forgot about rebuilding it (only build it) and new thing happened:
-------------- Clean: Debug in Testing (compiler: My New compiler because Ii can)---------------
Cleaned "Testing - Debug"
-------------- Build: Debug in Testing (compiler: My New compiler because Ii can)---------------
mingw32-g++.exe -Wall -g -IF:\C++\SDL\include\SDL2 -c F:\C++\Testing\main.cpp -o obj\Debug\main.o
mingw32-g++.exe -LF:\C++\SDL\lib -o bin\Debug\Testing.exe obj\Debug\main.o -lmingw32 -lSDL2main -lSDL2.dll -luser32 -lgdi32 -lwinmm -ldxguid
obj\Debug\main.o: In function `ZN9InitErrorC2Ev':
F:/C++/Testing/main.cpp:18: undefined reference to `SDL_GetError'
obj\Debug\main.o: In function `ZN3SDLC2Ej':
F:/C++/Testing/main.cpp:49: undefined reference to `SDL_Init'
F:/C++/Testing/main.cpp:52: undefined reference to `SDL_CreateWindowAndRenderer'
obj\Debug\main.o: In function `ZN3SDLD2Ev':
F:/C++/Testing/main.cpp:59: undefined reference to `SDL_DestroyWindow'
F:/C++/Testing/main.cpp:60: undefined reference to `SDL_DestroyRenderer'
F:/C++/Testing/main.cpp:61: undefined reference to `SDL_Quit'
obj\Debug\main.o: In function `ZN3SDL4drawEv':
F:/C++/Testing/main.cpp:67: undefined reference to `SDL_SetRenderDrawColor'
F:/C++/Testing/main.cpp:68: undefined reference to `SDL_RenderClear'
F:/C++/Testing/main.cpp:71: undefined reference to `SDL_RenderPresent'
F:/C++/Testing/main.cpp:89: undefined reference to `SDL_SetRenderDrawColor'
F:/C++/Testing/main.cpp:90: undefined reference to `SDL_RenderFillRect'
F:/C++/Testing/main.cpp:91: undefined reference to `SDL_RenderPresent'
F:/C++/Testing/main.cpp:92: undefined reference to `SDL_Delay'
F:/C++/IDE/MinGW/bin/../lib/gcc/mingw32/5.1.0/../../../libmingw32.a(main.o):main.c:(.text.startup+0xa7): undefined reference to `WinMain@16'
collect2.exe: error: ld returned 1 exit status
Process terminated with status 1 (0 minute(s), 3 second(s))
15 error(s), 0 warning(s) (0 minute(s), 3 second(s))
I am using MinGW compiler from the "codeblocks-17.12mingw-nosetup.zip" file.
Compiler settings:
Link libraries = mingw32, SDL2main, SDL2.dll, user32, gdi32, winmm, dxguid
SearchDirectories->compiler = F:\C++\SDL\include\SDL2
SearchDirectories->linker = F:\C++\SDL\lib
I think I am missing some libraries in the project folder.